A gardener pushes a wheelbarrow around the edges of a lawn. When she has finished, she is 5 m from her starting point. She has to pull upwards with a force of 300 N to lift the legs of the wheelbarrow off the ground. She pushes the wheelbarrow along the ground with a force of 100 N. Calculate how much work the gardener does in pushing the wheelbarrow around the lawn.

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).