The function is   feet/sec.

(a)

Find rate  when  is  feet .

.

ft/sec. 

(b)

Find rate when is feet .

ft/sec. 

(c)

Find limit as .

.

As tends to from the left hand side, the limit approaches to .

.

Verify the limit by the below table .

A limit in which   increases  without bound as approaches from the left  is called an infinite limit.

.

(a) ft/sec.

(b) ft/sec.

(c).