Ana exerts a force of 20 N on a volleyball that has a mass of 0.15 kg. What is the force that the volleyball exerts on Ana? 0.15 N
20 N
19.85 N
20.15 N
I think it's 20 but you can never be too sure.

Ithink it’s cancer risk

One splits the atoms and molecules  the other combines them

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.