The control of body temperature is extremely important during prolonged physical exercise. A cyclist trained in a hot climate and monitored their fluid and energy levels.
On one of the training days, the cyclist lost 4 200 cm34\text{ }200\text{ cm}^34 200 cm3 of water as sweat. Evaporation of 1 cm31\text{ cm}^31 cm3 of sweat requires 2.4 kJ2.4\text{ kJ}2.4 kJ of energy.
Calculate the energy the cyclist used for the evaporation of sweat on this day.
On a different day, the cyclist used 7 200 kJ7\text{ }200\text{ kJ}7 200 kJ of energy to evaporate sweat. The cyclist's total daily energy intake on that day was 24 000 kJ24\text{ }000\text{ kJ}24 000 kJ.
Calculate the percentage of the cyclist's energy intake used for the evaporation of sweat.