Tại sao phải sử dụng thời điểm như 1 yếu tố để xác định vị trí của một vật?

What is the mass of the same rock on the earth

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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.