1. A person has a mass of 77.0 kilograms (this is about 170 pounds). This person climbs three flights of stairs (a total vertical height of 12.9 meters) at a constant speed. Calculate how much work the person does. If the person climbs the three flights of stairs in 70.0 seconds, then what is their mechanical power output (this is equal to the rate at which work is being done) 

2. A 1450-kilogram car accelerates from 0 to 60 miles per hour in 7.35 seconds. Calculate the average power during this acceleration.