1) A rock is tossed straight up with a speed of 20 m/s. When it returns, it falls into a hole 11 m deep.
(a) What is the rock's velocity as it hits the bottom of the hole? ___________ m/s (downward)
(b) How long is the rock in the air, from the instant it is released until it hits the bottom of the hole? ___________ s
2)A snowboarder on a slope starts from rest and reaches a speed of 3.6 m/s after 7.7 s.
(a) What is the magnitude of the snowboarder's average acceleration?____________ m/s2
(b) How far does the snowboarder travel in this time? __________m