The water diet requires one to drink two cups of water every half hour from when one gets up until one goes to bed, but otherwise allows one to eat whatever one likes. Four adult volunteers agree to test the diet. They are weighed prior to beginning the diet and after six weeks on the diet. The weights (in pounds) are

Person 1 2 3 4 Mean SD
Weight before diet 180 125 240 150 173.75 49.56
Weight after six weeks 170 130 215 152 166.75 36.09
Difference 10 -5 25 -2 7 13.64

The goal is to test whether the water 'diet' leads to a mean weight loss.

What is the null hypothesis? Let subscript 1 indicate the measurement before the diet, and subscript 2 the measurement after six weeks.

(Pick letter corresponding to the best answer.)

a - H0: x?1-x?2 = 7
b - H0: ?1-?2 = 7
c - H0: x?1-x?2 = 0
d - H0: ?1-?2 = 0

true

explanation:

step-by-step explanation:

it will be a cylinder. with a diameter of 8 and 4 single pieces high

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240