A bicyclist of mass 75 kg (including the bicycle) can coast down a 4.0° hill at a steady speed of 12

A bicyclist of mass 75 kg (including the
bicycle) can coast down a 4.0° hill at a steady speed of 12 km/h. Pumping hard,
the cyclist can descend the hill at a speed of 32 km/h. Using the same power,
at what speed can the cyclist climb the same hill? Assume the force of friction
is proportional to the square of the speed v; that is, Ffr = bv2,
where b is a constant.