Question

Which scenario can be modeled by a linear function?
A - The area of a circle A can be determined using length of the diameter of the circle D
B - the number of gallons of water used W is based on the number of minutes T a fire house is turned on if the house uses water at a constant rate
C - The number of televisions T a store sells each week w is 10, 15, 22, 17, and 18 televisions respectively for the first five weeks the store is open
D - The population of ants in a colony P starts with 1,000 ants and grows by 3% every week x

I think the answer is A

Answer 1

No, pi (D^/4) = pi R^2 is NOT linear. It is times the variable SQUARED, not proportional to the variable^1
Linear means y = m x + b
in this problem b is zero it turns out for the right answer
y = m x

Answer 2

typo pi (D^2 / 4)