As per energy conservation in the reversible engine we can say
[tex]Q_2 + W = Q_1[/tex]
here we know that
[tex]Q_2 = 3300 kJ/h[/tex]
[tex]Q_1 = 4800 kJ/h[/tex]
now from above equation
[tex]3300 + W = 4800[/tex]
[tex]W = 1500 kJ/h[/tex]
now we can convert it into kW
[tex]W = 1500\times \frac{kJ}{3600s}[/tex]
[tex]W = 0.42 kW[/tex]
so above is the power input to the refrigerator
now to find COP we know that
[tex]COP = \frac{Q_2}{W}[/tex]
[tex]COP = \frac{3300}{1500} = 2.2[/tex]
so COP of refrigerator is 2.2