Muscles in the human body are not perfectly efficient. In fact, only about 20.0% of the Calories we burn during physical activity go towards mechanical work (i.e., moving the body around) - the rest is converted to heat. Estimate how many Calories a 85.0 kg person will burn if they climb to the top the Empire State Building, which is 443 meters tall. Hint: you need to exert a force that counteracts gravity to move upwards - calculate the work done by this force! Also, use the unit conversion 1 Cal = 4184 J.
