[填空题]
A stone is thrown vertically upwa5 p g1 rt*1au( vsf6vjuz(nuh3rd with a speed yry b- 1ldqs3:of 12.0 m/s from the edge of a cliff 70.0 m high (Filbyqr y d-1s3:g. 2–34).
(a) How much later does it reach the bottom of the cliff? t = s
(b) What is its speed just before hitting? m/s
(c) What total distance did it travel? m