2. A boy drops a stone of mass 200 g from a height of 2 m. a) What is the momentum of the stone just before it hits the
floor?
b) What is the impulse of the stone?
c) The stone comes to a halt in 0.05 s. What is the force exerted
on the stone?​

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.

Answerinternal combustion engine fuel;