Your friend claims to have constructed an engine that operates between two reservoirs at 500 K and 350 K. She says that, in each cycle, the engine extracts 6000 J of heat from the high temperature reservoir, rejects 3900 J of heat to the low temperature reservoir and performs 2100 J of work. Would you invest in this engine

answer: option c.

explanation:

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min