When the height of the cylinder increased by a factor of 5from 100 m to 500 m, what happened to the cylinder's
gravitational potential energy?
It decreased by a factor of 10
It decreased by a factor of 5.
It increased by a factor of 5.
It increased by a factor of 10

Rain is pulled by gravity which is a non contact force

If the heat engine is a perfect carnot cycle engine, thenefficiency = (t2-t1)/t2   where t1=temperature of cold reservoir ( ° k) = 135            t2=temperature of hot reservoir ( ° k)   = 325thereforeefficiency = (t2-t1)/t2 = (325-135)/325 = 0.5846 = 58%  note: this is the theoretical maximum efficiency of a perfect heat engine.   real-life engines do not achieve this value.