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Identical marbles are released from the same height on each of the following four frictionless ramps . compare the speed of the marbles at the end of each ramp. explain your reasoning

Using gravity, an elephant can pull a mouse towards it from the ground. true or false explain why. will give brainliest if answered fast and the best explanation

Refrigerant-134a flows through a carnot heat pump cycle at 0.5 kg/s. it is known that the maximum absolute temperature in the cycle is 1.1 times the minimum absolute temperature, and the net power input to the cycle is 2.5 kw. if the refrigerant changes from a saturated vapor to a saturated liquid during the heat rejection process, determine the maximum magnitude of the enthalpy of vaporization for this process in kj/kg (with 3 significant figures).