Which of the following measurements is used to measure the distance between astronomical bodies? speed of light speed of sound speed of spacecraft speed of rotation of earth

Combination   of  the orbit of the earth  and the speed of light.
distances   are measured in light years.

Ithink the answers is b i hope it my friend message me if i’m wrong and i’ll change my answer and fix it for you

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.