Please hurry Theo was doing research to support the claim that
exercise increases heart and lung health. He had 50
people do a rigorous exercise program. Each week, for
six months, he tested their heart and respiratory rate. He
determined that exercise does increase heart and lung
health.

Which best describes his claim?

A-It is valid because he used multiple trials.

B-It is invalid because he did not have a control group

C-It is invalid because his sample size was small.

D- It is valid because he controlled the exercise
program.

depends on how many days you are talking about

step-by-step explanation:

answer: the price of one pound cabbage = $ 0.8

the point (10,8) represents that the cost of 10 pounds cabbage is $ 8

step-by-step explanation:

since, here is a proportional relation between the number of pounds of cabbage (x) and the price in dollars (y).

therefore, we can write,

⇒ y = k x

where k is the constant of proportionality.

now, point (5,4) is in the line.

thus, it will satisfies the above equation of line.

⇒ 4 = 5 k

⇒ k = 0.8

thus, the equation of the line is,

y = 0.8 x

a) for x = 1,

y = 0.8

therefore, the cost of one pound of cabbage is 0.8 dollars.

b) in the below graph (10,8) represents that the cost of 10 pounds of cabbage is 8 dollars.

more detail

step-by-step explanation: