An inventor is applying for a patent. He claims his new heat engine can produce 1,200 J of work for every 1,800 J of heat applied to it. In 3–5 sentences, evaluate this claim after solving for η.

the answer is to check all of them! they all apply well at least i think so!

elctricity and magnet is conversion to it

one "light year" is the distance that light travels, through vacuum, in one julian year.   that's 365.25 days, of 24 hours each.