In the scientific method, questioning does which of the following? Defines the problem to be explored
Challenges the work of other scientists
Articulates the results of an experiment
Creates doubt within the scientific community

True.it is better to buy a washer with a higher efficiency rating

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.