A lake initially contains 20,000 kg of water and has a uniform temperature of 20°C. The ambient pressure is P = 1 bar. During the course of a day, the following events affecting the lake occur:

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200 kg of rain falls into the lake. The rainwater has a temperature of 25°C. Some water evaporates from the lake. Heat is both added to (sunlight) and removed from (convection into the cooler air) the lake. If you need the heat capacity of LIQUID water, use the approximation C₂ C₂-4.184 J/g °C. A. Find a reasonable estimate of the velocity of a raindrop and determine the kinetic energy of the rain when it strikes the lake. Is the kinetic energy significant compared to the enthalpy? B. The surface of the lake is at T = 20°C and P = 1 bar. The enthalpy of water vapor at T = 20°C and P = 1 bar is not in the steam tables. You could