A stone is dropped from the upper observation deck (the Space Deck) of the CN Tower, 450 meters above the ground.

(a) Find the distance $s$ of the stone above ground level at time $t$, where time is measured in seconds.

$s(t) =$

(b) How long (in seconds) does it take the stone to reach the ground?

Time needed = seconds

(c) With what velocity (in m/s) does it strike the ground?

Velocity = meters per second

(d) If the stone is thrown downward with a speed of 3 m/s, how long does it take (in seconds) for the stone to reach the ground?

Time needed = seconds