A person biking down a 5° slope without pedaling or braking noticed that her speed is constant at 25 km/h. Approximately what power does she need to bike up this hill at the same speed if her weight including the bike is 65 kg?
a) Nobody can bike down the hill at constant speed without braking.
b) 800 W
c) 1400 W
d) 400 W
e) 2800 W