a boy throws a rock straight up into the air. it reaches the highest point of its flight after 2.5 seconds. how fast was the rock going when it left the boys hand?

6–48 bananas are to be cooled from 24 to 138c at a rate of 215 kg/h by a refrigeration system. the power input to the refrigerator is 1.4 kw. determine the rate of cooling, in kj/ min, and the cop of the refrigerator. the specific heat of banana above freezing is 3.35 kj/kg·8c.