[TheToby]

Does anyone know how to approach this question?  My teacher only covered the topic briefly in class and now we are going to be having a test soon.  I do not understand how they answered the question.  One question is

A Carnot refrigerator operating between -20⁰C and +20⁰C extracts heat from a cold reservoir at the rate of 200 J/s.

What are (a) the coefficient of performance of the refrigerator,

(b) the rate at which work is done on the refrigerator, and

(c) the rate at which heat is exhausted to the hot side?


Any help would be greatly appreciated.