An air conditioner operating at steady state maintains a dwelling at 20 degrees Celsius on a day when the outside temperature is 35 degrees Celsius. Energy is removed by heat transfer from the dwelling at a rate of 2800 J/s while the air conditioner's power input is .8 kW. Determine (a) the coefficient of performances of the air conditioner and (b) the power input required by a reversible refrigeration cycle providing the same cooling effect while operating between hot and cold reservoirs at 35 degrees Celsius and 20 degrees Celsius, respectively.