Question

Answer and please show work!

Answer 1

0.3 ft/h

Explanation:

At hour 18, the depth is 21 ft.

At hour 9, the depth is 18 ft.

Then the average rate of change is ...

(change in depth)/(change in time) =

(21 ft -18 ft)/(18 h -9 h) = (3 ft)/(9 h) = 1/3 ft/h ≈ 0.3333 ft/h ≈ 0.3 ft/h