[填空题]
A stone is thrown verticallyt(-yn1cbd*qxna1nbp 6 +l zw. upward with a speed of eb+;+ncha co7 bhr u+,$36 \; m/s$ from the edge of a cliff 90.0 m high (a) How much later does it reach the bottom of the cliff? $s$ (b) What is its speed just before hitting? $m/s$ (c) What total distance did it travel? $m$