This train has reached a speed of 550 km/hr. Assume the mass of the train is 1.33 x10^5 kg and the unbalanced force to accelerate the train to its top speed is 7.07 x 10^4 N. What is the train’s acceleration?

This is the answer of your question

Inner peace.. jk it's  a stable electron configuration

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.