Are you sure those are the options to that description?
I did the test and the options were:
A) f(x) = 4x + 14; 0 ≤ y ≤ 4
B) f(x) = 4x + 18; 0 ≤ y ≤ 4
C) f(x) = 4x + 14; 18 ≤ y ≤ 30
D) f(x) = 4x + 18; 18 ≤ y ≤ 30
If those are the options, then the answer would be:
Answer:
D) f(x) = 4x + 18; 18 ≤ y ≤ 30
Explanation:
It would be that because if they want to increase by 4 customers every week you would attached that to x and since they started out with 18 customers they add 18 to the total weeks.