A cyclist with a total skin area of 1.5 m2 is riding a bicycle on a day when the air temperature is 20oC and her skin temperature is 34oC. The cyclist does work at about 200 W (moving the pedals) but her efficiency is only about in terms of converting energy into mechanical work. Estimate the amount of water this cyclist must evaporate per hour (through perspiration) to get rid of the excess body heat she produces. Assume a skin emissivity of 0.70.