Given the formula:

Let's solve for the following:
• (a). What is its height after 4 seconds?
To find the height after 4 seconds, substitute 4 for t and solve for h(4):

The height after 4 seconds is 230 feet.
• (b). What is its velocity after 4 seconds?
To find the velocity, we have:

Now find the derivative:

Substitute 4 for t and solve for v(4):

Therefore, after 4 seconds, the velocity is 0 m/s.
ANSWER:
a) 230 ft
b) 0