Please help !!!!!!!!!!!

The 95 percent confidence interval that the true mean lead level of crows in the region is between 4.4157 and 5.3843.

What is a confidence interval?

An estimated range for an unknown parameter is known as a confidence interval. The 95% confidence level is the most popular, however other levels, such as 90% or 99%, are occasionally used when computing confidence intervals.

Here, we have

Given:  the mean lead level of the 23 crows in the sample was 4.90 ppm and the standard deviation was 1.12 ppm.

= x ± t×s/√n

= 4.90 ± (2.074)×1.12/√23

= (4.4157, 5.3843)

Hence, the 95 percent confidence interval that the true mean lead level of crows in the region is between 4.4157 and 5.3843.

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Step-by-step explanation:

If the area of the bean field is 440ft^2 and each bag of fertilizer covers 100 ft^2, then Farmer Bob will need:

440 ft^2 / 100 ft^2 per bag = 4.4 bags of fertilizer

Since Farmer Bob can't buy a fraction of a bag, he will need to round up to 5 bags of fertilizer.

The total cost of the fertilizer will be the number of bags multiplied by the cost per bag, which is $5.50. Therefore, the total cost of the fertilizer will be:

5 bags x $5.50 per bag = $27.50

Answer:

58

Step-by-step explanation:

We see that both sides around x are the same length, 6.2. This tells us our triangle is an isosceles triangle, which means two sides are the same lengths. This also tells us that two angles will be equal to each other.

The angle other than x and 61, will be equivalent to 61.

We also know that a triangle's angles equal 180. So,

180 - 61 = 119

119 - 61 = 58

x = 58

Sorry if my explaination isn't fully clear, it's hard to type it out and explain!

Therefore, the probability that on the next page, the author will make at most two word processing errors is 0.99207367.

To find the probability of making word processing errors, we must use Poisson Distribution.

What is Poisson Distribution?

A Poisson distribution is a probability distribution that estimates the number of occurrences of an event in a fixed time or space interval.

It is used to model a situation where events occur randomly and independently over a fixed period or area.

The Poisson distribution's primary assumptions are that events are rare, random, and that one event does not affect another event's outcome. The Poisson distribution is useful in predicting the number of occurrences of a specific event in a given time or space interval. This distribution is useful in several fields, including finance, insurance, and public health.Now let's solve the given problem,

The probability that there are no word processing errors is given by[tex]:P (X = 0) = e^ -μμ = 200/500 = 0.4[/tex] (average number of errors per page = 2/5)P (X = 0) = e^ -0.4 = 0.67032005Now, the probability that there are 2 or fewer errors is given by:[tex]P (X ≤ 2) = ΣP (X = i) i = 0 to 2P (X ≤ 2) = P (X = 0) + P (X = 1) + P (X = 2)P (X ≤ 2) = 0.67032005 + 0.26812802 + 0.0536256P (X ≤ 2) = 0.99207367[/tex]

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The equation for the line of the best fit in slope-intercept form is y = mx + b, where m is the slope of the line and b is the y-intercept of the line.

An equation is a mathematical statement that asserts the equality of two expressions. It consists of two expressions, separated by an equal sign, that have the same value. Equations are used in algebra to solve unknown values and to describe the relationship between different variables. Equations are also used to determine the unknown value of a single variable in a given equation.

To calculate m and b, we first need to calculate the sum of the products of the x and y values (Σxy), the sum of the x values (Σx), the sum of the y values (Σy), and the sum of the squares of the x values (Σx2).

Σxy = x1y1 + x2y2 + x3y3 + ... + xnyn
Σx = x1 + x2 + x3 + ... + xn
Σy = y1 + y2 + y3 + ... + yn
Σx2 = x12 + x22 + x32 + ... + xn2

Then, we can calculate the slope m of the line using the following equation:
m = (nΣxy - ΣxΣy) / (nΣx2 - (Σx)2)

Finally, we can calculate the y-intercept b of the line using the following equation:
b = (Σy - mΣx) / n

Once we have calculated the slope m and the y-intercept b, we can write the equation for the line of the best fit in slope-intercept form: y = mx + b.

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Since the minimum upward velοcity cannοt be negative, the answer is (A) 7.5 feet per secοnd. If we had taken the absοlute value οf the velοcity, the answer wοuld be (B) 19.7 feet per secοnd.

Velοcity is a physical quantity that describes the rate οf change οf an οbject's pοsitiοn with respect tο time. It is a vectοr quantity that has bοth magnitude and directiοn, with the magnitude representing the speed οf the οbject and the directiοn indicating its mοtiοn. In οther wοrds, velοcity tells us hοw fast an οbject is mοving and in which directiοn.

Tο find the minimum upward velοcity needed tο reach the branch, we can use the cοnservatiοn οf energy principle. At the height οf 5.5 feet, the weight has pοtential energy, which will be cοnverted tο kinetic energy as it falls. When the weight reaches the branch at a height οf 15 feet, all οf its initial pοtential energy will be cοnverted tο kinetic energy. Therefοre, we can equate the pοtential energy at the initial height with the kinetic energy at the final height:

[tex]mgh = (1/2)mv^2[/tex]

There m is the mass οf the weight (which cancels οut), g is the acceleratiοn due tο gravity (32 ft/s²), h is the initial height (5.5 ft), and v is the velοcity at the final height (15 ft).

Substituting the values, we get:

(32 ft/s²) * (15 ft - 5.5 ft) = (1/2) * v²

v² = 2 * (32 ft/s²) * (15 ft - 5.5 ft) = 800 ft²/s²

Taking the square rοοt οf bοth sides gives:

v = √(800) = 28.28 ft/s

Hοwever, we need the minimum upward velοcity, sο we must subtract the initial dοwnward velοcity (due tο gravity) οf 32 ft/s:

minimum upward velοcity = v - g = 28.28 ft/s - 32 ft/s = -3.72 ft/s

Since the minimum upward velοcity cannοt be negative, the answer is (A) 7.5 feet per secοnd, which is the magnitude οf the upward velοcity.

Nοte: If we had taken the absοlute value οf the velοcity, the answer wοuld be (B) 19.7 feet per secοnd. Hοwever, the minimum upward velοcity is the cοrrect answer in this cοntext.

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Answer: Third option

Step-by-step explanation:

[tex](a^{b})^{c}[/tex] = [tex]a^{b\times c}[/tex] = [tex]a^{bc}[/tex]

[tex]\frac{(m^{5}n)^{4}}{(pq^{2})^{4}}[/tex] = [tex]\frac{m^{20}n^{4}}{p^{4}q^{8}}[/tex]

Answer: We can only determine the cost for each burger if we know the total cost of all the ground beef. Let's assume that the ground beef costs $C in total.

If Coach Miller is using all the ground beef to grill 17 burgers, then the cost of each burger is:

Cost per burger = Total cost of ground beef / Number of burgers

We know that the total cost of ground beef is $C, and we know that there are 17 burgers. Substituting these values into the formula gives:

Cost per burger = C / 17

Therefore, the cost for each burger is C/17. We cannot determine the numerical value of C or the cost per burger without additional information.

Step-by-step explanation:

The roots of the equation x² - 5x + k are z = (5/a - 3)/2 and z+3 = (5/a + 3)/2, and the value of k is 9/4.

The roots of an equation are the values of the variable that satisfy the equation and make it true. In the case of a quadratic equation of the form ax² + bx + c = 0, the roots are the values of x that satisfy the equation and make it equal to zero.

Given:  z and z+3 are the roots of the equation x² - 5x + k

The sum of the roots z and z+3 is:

z + (z + 3) = 2z + 3

And the product of the roots z and z+3 is:

z (z + 3) = z² + 3z

By Vieta's formulas, we know that the sum of the roots of a quadratic equation ax² + bx + c = 0 is -b/a and the product of the roots is c/a. Therefore, we can equate these expressions to the sum and product of the roots of the given equation:

2z + 3 = 5/a (since b = -5 and a = 1)

z² + 3z = k/a (since c = k and a = 1)

Solving for z in the first equation, we get:

2z = 5/a - 3

z = (5/a - 3)/2

Substituting this value of z into the second equation, we get:

[(5/a - 3)/2]² + 3[(5/a - 3)/2] = k/a

Simplifying and solving for k, we get:

k = a[(5/a - 3)/2]² + 3a[(5/a - 3)/2]

= (5a - 9a + 18)/4

= 9/4

Therefore, the roots of the equation x² - 5x + k are z = (5/a - 3)/2 and z+3 = (5/a + 3)/2, and the value of k is 9/4.

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The heights of the passenger as they move on the Colossus Ferris wheel described by the specified sine function are;

2. (a) 22 times

(b) 180 feet which is the highest point on the ride

3. (a) 15 feet

(b) The last passenger will not need to weight

A sine function is a mathematical function that describes a smooth repetitive oscillation. The sine function is a periodic function which repeats itself after certain interval. The sine function is the ratio of the opposite side to the hypotenuse side of a right triangle.

2. (a) The period of the sine function model, for the height, h = -82.5×cos(3·π·t) + 97.5 is 2·π/3. Therefore, the last passenger who boarded the ride makes a completer loop on the Ferris wheel every **2/3 minutes**. Since the duration of the ride is 15 minutes, the number of complete loops the passenger makes = 15/(2/3) = 22.5

(b) When the ride ends, the height of the last passenger can be found by evaluating the specified sine function at t = 15 minutes (the ride lasts for 15 minutes).

Therefore; h = -82.5 × cos(3 × π × 15) + 97.5 = 180.

3. (a) The time of operation of the ride when the power outage occurs is t = 6 minutes. The height of the last passenger at the time of the power outage is; h = -82.5 × cos(3 × π × 6) + 97.5 = 15

(b) The last passenger to board the ride will not need to weight in order to exit the ride. This is because the height of the last passenger at the moment of the power outage is 15 feet, which is the initial height of the passenger when they board the ride. Therefore, the last passenger will be at the same height as the ground, and can exit the ride without waiting.

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Applying mathematical operations, "Four times the sum of 5 and some number is 20," the number is 0.

The mathematical operations include addition, subtraction, division, and multiplication.

Mathematical or algebraic operations use mathematical operands to manipulate values, variables, constants, and numbers to solve mathematical problems.

Zero is considered to be a neutral number since it is neither positive nor positive.

Zero is important as a number placeholder.

4 (5 + x) = 20

20 + 4x = 20

4x = 20 - 20

4x = 0

x = 0

Thus, in the mathematical operations of multiplying the sum of 5 and some number by 4, the applicable number is zero.

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Answer:

  1/2

Step-by-step explanation:

You want to know the average rate of change of f(x) = 1/2x -7 on the interval [2, 10].

A linear function has the same rate of change everywhere. Its instantaneous rate of change, average rate of change, and slope are all the same constant.

The given function is written in slope-intercept form, so we can identify the slope as the coefficient of x: 1/2.

The average rate of change is 1/2.

__

Additional comment

If you feel the need to "show work", you can evaluate ...

  AROC = (f(10) -f(2))/(10 -2) = (-2 -(-6))/8 = 4/8 = 1/2

According to the question the height of the ladder is 34.641 feet, or approximately 19.98 feet.

Height is the measure of vertical distance, either how "tall" something or someone is, or the distance between the top and bottom of an object. It is measured in either centimeters, meters, or feet and inches, and can be used to describe the elevation of land or the altitude of an aircraft.

Let x be the height of the ladder.
For a 20-foot ladder at an angle of 45°, we have the following trigonometric equation:
tan(45°) = x/20
Solving for x we get:
x = 20tan(45°)
x = 20 × 1
x = 20
Therefore, the height of the ladder is 20 feet.
For a 20-foot ladder at an angle of 75°, we have the following trigonometric equation:
tan(75°) = x/20
Solving for x we get:
x = 20tan(75°)
x = 20 × 1.73205
x = 34.641
Therefore, the height of the ladder is 34.641 feet, or approximately 19.98 feet.

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The range of height can be determined by trigonometric ratios and the rage is 20ft to 74.6 ft(approximately).

What is Trigonometric Ratios?

Trigonometric Ratios are  based on the value of the ratio of sides of a right-angled triangle where Hypotenuse is the longest side Perpendicular is opposite side to the angle and Base is the Adjacent side to the angle. The ratios of these three sides of a right-angled triangle with respect to any of its acute angles are known as the trigonometric ratios of that particular angle.

Given that a ladder should not be set up at an angle less than 45 degrees or at an angle greater than 75 degrees.

The ladder is 20 foot.

here the trigonometric function tangent will be used.

By the formula, tan Ф = Perpendicular/ adjacent side [ where Ф is the acute angle]

Let, the height of the ladder is x foot.

Then by formula of trigonometric ratio,

tan 45° = x/20

⇒ x/20 =1 [ since tan 45° =1 ]

⇒ x= 20

Again,

tan 75° = x/ 20

⇒ x= 20× tan 75°

⇒ x= 74.6 [ since tan 75° = 3.732]

Hence, the range of height is 20 foot to 74.6 foot ( approx ).

The rough diagram is attached below.

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There are no critical numbers for the function f(x) = 2x³ + x² + 4x. This is because the discriminant (b² - 4ac) is negative.

1. Calculate the derivative of the function with respect to x (f'(x)). This will help us identify where the function has a critical point (maximum, minimum, or inflection point).

f'(x) = [tex]\frac{d}{dx} (2x^{3} + x^{2} + 4x)[/tex]

2. Use the power rule for differentiation to find the derivative of each term.
f'(x) = (3 * 2)x² + (2 * 1)x + 4

3. Simplify the derivative.
f'(x) = 6x² + 2x + 4

4. To find the critical numbers, set the derivative equal to zero and solve for x.
6x² + 2x + 4 = 0

5. To solve for x, we can use the quadratic formula:
x = [tex]\frac{-b\sqrt{(b^{2} - 4ac) } }{2a}[/tex]
where a = 6, b = 2, and c = 4.

6. Plug the values of a, b, and c into the quadratic formula:
x = [tex]\frac{-2 +\sqrt{(2^{2} - 4(6)(4)) } }{2 * 6}[/tex]

7. Simplify the expression:
x =[tex]\frac{-2 +\sqrt{(92) } }{12}[/tex]

8. Since the discriminant (b² - 4ac) is negative, there are no real solutions for x, meaning there are no critical numbers for the given function.

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in this particular data set, there is only one value that appears most frequently, which is 5.

What are statistics?

Statistics is a branch of mathematics that deals with the collection, analysis, interpretation, presentation, and organization of data. It provides a set of methods and tools for extracting meaningful insights and making decisions based on data.

In statistics, the mοde is the value that is repeatedly οccurring in a given set. We can alsο say that the value οr number in a data set, which has a high frequency οr appears mοre frequently, is called mοde οr mοdal value. It is οne οf the three measures οf central tendency, apart frοm mean and median. Fοr example, the mοde οf the set {3, 7, 8, 8, 9}, is 8.

Therefοre, fοr a finite number οf οbservatiοns, we can easily find the mοde. A set οf values may have οne mοde οr mοre than οne mοde οr nο mοde at all.

In the given data 5 has the maximum frequency so 5 is style mode of the given data

Mode=5

Therefore, in this particular data set, there is only one value that appears most frequently, which is 5.

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Answer:

≈ 31,53 cm

Step-by-step explanation:

[tex]2\pi \times r = 198[/tex]

[tex]r = \frac{198}{2\pi} = \frac{198}{2 \times 3.14} = \frac{198}{6. 28} ≈ 31.53[/tex]

Answer:x^2+12x-28=01. 12/2=62. (x+6)^2=x^2+12x+363. If we subtract 64 from this expression it becomesx^2+12x+36-64=x^2+12x-28 and so equals 0We now have (x+6)^2-64=0This is our old friend a^2-b^2=(a+b)(a-b)(x+6)^2-8^2=(x+6+8)(x+6-8)=(x+14)(x-2)=0 and so x=-14 or x=2

Step-by-step explanation:

Answer:

Side length of equilateral triangle is = 29 units

In geometry, an equilateral triangle is a triangle that has all its sides equal in length.

3 given lengths are

3x+8 , 5x - 6 , 2x +15

so,

[tex] \rm \: 3x + 8 = 5x - 6 = 2x + 15[/tex]

consider 2 sides,

[tex] \rm \implies 3x + 8 = 2x + 15[/tex]

[tex] \rm \implies 3x - 2x = 15 - 8[/tex]

[tex] \rm \implies x= 7[/tex]

so,

[tex] \rm \: 3x + 8 = 3 \times 7 + 8 = 29[/tex]

As equilateral triangle

3x+8 = 5x - 6 = 2x +15 = 29

The sides of a triangle are straight lines that are joined by the three vertices of the triangle.

so,

Side,length of equilateral triangle is 29 units

Number of Sides = 3

Number of angles = 3

Each interior angle = 60

Each exterior angle = 120

Perimeter = 3 times of side-length

Area = √3/ 4 x (side)2

Height = √3 (side)/2

Here,

AC ≅ AB

→ 5x -6 = 3x+8

→ 5x - 3x = 8+6

→ 2x = 14

→ x = 14/2

→ x = 7

Now Putting the value of x

AC = 5x - 6

= 5(7) -6

= 35 -6

= 29

AB = 3x + 8

= 3(7) +8

= 21 + 8

= 29

BC = 2x + 15

=2(7)+15

= 14 + 15

= 29

Thus,

Area of triangle

[tex] \sf \: \frac{1}{2}bh [/tex]

Area of equilateral triangle

[tex] \sf \: \frac{ \sqrt{3} }{4} {a}^{2} [/tex]

Area of Isosceles Triangle

[tex] \sf \: \frac{b}{4} \sqrt{ {4a}^{2} - {b}^{2} } [/tex]

Answer:

$1.60

Step-by-step explanation:

This is a very simple question

First start off with 1.2/0.75

1.2 divided by 0.75 = 1.6

Add a zero on to 1.6 and you have your answer of

$1.60

Volume is a measure of the amount of space occupied by a three-dimensional object. It is typically expressed in cubic units, such as cubic meters, cubic feet, or cubic centimeters. The volume of an object can be calculated by measuring its dimensions and applying the appropriate formula.

In the given questions,

1.The height of the can will increase by a factor of 2. The marketing team wants to make the new can as large as possible given their budget, and since the cost of materials for the new can is limited to $0.16, they need to use the least amount of material possible. The volume of a cylinder is given by V = πr²h, so to maximize the volume of the can while using a limited amount of material, they should increase the height of the can while keeping the radius the same. Since the volume of a cylinder is proportional to the height, doubling the height will double the volume.

2.The radius of the can will remain the same. Since the marketing team wants to make the new can as large as possible given their budget, they need to use the least amount of material possible. Increasing the radius of the can will increase the amount of material needed to make the can, which will increase the cost of materials.

3.The cans resemble a cylinder. The actual can may have minor differences in shape due to manufacturing processes or imperfections.

4.The cost for materials for the jumbo can will be $0.16, and the cost to fill the can with juice will be $0.27. Therefore, the total cost for materials and juice fill will be $0.43 per jumbo can.

5.Other factors that might cause the total cost to be different could include the cost of labor to manufacture the cans, the cost of transporting the materials and finished products, and fluctuations in the cost of materials or juice. Additionally, the marketing team may need to consider the price point of the jumbo can and the demand for the product at that price point.

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Answer:

Step-by-step explanation:

Answer:

5805 words

Step-by-step explanation:

2 hours × 60 minutes/hour = 120 minutes

120 minutes + 15 minutes = 135 minutes

2 hours and 15 minutes = 135 minutes

135 minutes × 43 words/minute = 5805 words

Phoebe has 71.8 percentage of the total cost of the swimming lessons.

A number can be expressed as a fraction of 100 using a percentage. It is often represented by the symbol "%". Percentages are commonly used to express a proportion or rate of change, particularly in business, finance, and science. For example, if a student scores 90 out of 100 on an exam, their percentage score is 90%.  

The total cost of 65 swimming lessons at £30 each is:

65 x £30 = £1950

Percentage = (Amount / Total) x 100

where "Amount" is the amount that Phoebe has, and "Total" is the total cost of the swimming lessons.

Plugging in the numbers, we get:

Percentage = (1400 / 1950) x 100

Percentage = 0.7179487 x 100

Percentage = 71.8 (rounded to 1 decimal place)

Therefore, Phoebe has 71.8% of the total cost of the swimming lessons.

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Answer:

LM = 5

Step-by-step explanation:

A secant is a straight line that intersects a circle at two points.

A segment is part of a line that connects two points.

The product of the measures of one secant segment and its external part is equal to the product of the measures of the other secant segment and its external part.

The given diagram shows two secant segments LN and PN that intersect at exterior point N.  Their external parts are MN and ON, respectively.

Therefore, according to the Intersecting Secants Theorem:

[tex]\implies \sf LN \cdot MN =PN \cdot ON[/tex]

Given values:

Substitute the values into the equation and solve for x:

[tex]\implies \sf LN \cdot MN =PN \cdot ON[/tex]

[tex]\implies (x+1)\cdot 3=(x-1)\cdot 4[/tex]

[tex]\implies 3x+3=4x-4[/tex]

[tex]\implies 4x-4=3x+3[/tex]

[tex]\implies 4x-4-3x=3x+3-3x[/tex]

[tex]\implies x-4=3[/tex]

[tex]\implies x-4+4=3+4[/tex]

[tex]\implies x=7[/tex]

To determine the length of LM, substitute the found value of x into the expression for the line segment:

[tex]\implies \overline{LM}=7-2=5[/tex]

Therefore, the length of LM is 5.

Answer:

x^3 + 5x - 23

Step-by-step explanation:

(Q+R)(x) is the same as Q(x) + R(x).

you just add them like so:

(x^3 - 9x^2 - 14) + (9x^2 + 5x - 9)

= x^3 + 5x - 23

Answer:

13

Step-by-step explanation:

0.3*65

=19.5 pounds

[tex]\frac{2}{10} =0.2\\0.2*65=13[/tex]

Answer:

54 , 90

Step-by-step explanation:

Let John = 10x
Let Anvil = 6x

10x = 36 + 6x

10 - 6x = 36

4x = 36

x=9

Anvil = 6*9 = 54
John = 10*9 = 90

Answer: 230

Step-by-step explanation: The first thing you need to do is add 1 inch to the length and width. The starting lenght is 22, and that becomes 23. The starting width is 9, and that becomes 10. The new measurements are 23 by 10. To find area you multiply length by width. 23 times 10 gives you an answer of 230. I hope that helped!

Collecting data on 83,359 grade-point averages would be a significant undertaking and a 99% confidence level, especially if the data had to be collected in a short amount of time or if there were limited resources available for data collection.

To determine the sample size needed to estimate the population mean within a certain margin of error, we can use the formula:

[tex]n = (Z^2 * sigma^2) / E^2[/tex]

where n is the sample size, Z is the Z-score for the desired confidence level (in this case, 2.576 for a 99% confidence level), sigma is the population standard deviation (in this case, estimated as 1.25 using the range rule of thumb), and E is the desired margin of error (in this case, 0.01).

Plugging in the values, we get:

[tex]n = (2.576^2 * 1.25^2) / 0.01^2 = 83,358.08[/tex]

So we would need a sample size of at least 83,359 to estimate the population mean with a margin of error of 0.01 and a 99% confidence level.

However, this sample size may not be practical depending on the resources available. Collecting data on 83,359 grade-point averages would be a significant undertaking, especially if the data had to be collected in a short amount of time or if there were limited resources available for data collection.

In practice, researchers often use statistical software to calculate sample sizes based on the desired margin of error, confidence level, and population standard deviation. This allows them to determine a more realistic sample size based on the specific context of their study.

In summary, while the formula for determining sample size can provide an estimate of the number of observations needed to estimate the population mean with a certain level of precision, other factors such as the availability of resources must also be considered when determining a practical sample size.

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Answer:

1/5 is the right answer in my opinion but I'm not sure