Answer
a) $240$ ft/sec.
b) $1600$ ft
Work Step by Step
a). Using the formula for velocity, we have:
Velocity = Initial velocity - (acceleration due to gravity $\times$ time)
Velocity = $400$ ft/sec - ($32 ft/sec^{2}$ $\times 5$ sec)
Velocity = $400$ ft/sec - $160$ ft/sec
Velocity = $240$ ft/sec
b).
Displacement = Initial velocity $\times$ time - (1/2) $\times$ acceleration $\times$ time$^{2}$
Displacement = $400 \times 5 - (1/2) \times 32 \times (5^{2})$
Displacement = $2000 - (1/2) \times 32 \times 25$
Displacement = $2000 - 16 \times 25$
Displacement = $2000 - 400$
Displacement = $1600$ ft.
