Answer:
b). (0, 4)
if you need an explanation, comment, and I will put one in for you :)
ohh hiiii...................
the secound option :)
20
Step-by-step explanation:
just substitute 0 for time in your equation, you will get 20.
on the interval 0 ≤ x ≤ 7, for maximum value, f'(x) = 0.