The equation $\beta = \frac{Q_2}{Q_1 - Q_2}$ is true or false?

Which of the following can be the coefficient of performance of a refrigerator?

$A$ household refrigerator with a coefficient of performance $1.2$ removes heat from the refrigerated space at the rate of $60 \ kJ/min$. What would be the cost of running this fridge for one month $(30 \ days)$, assuming it is used for $4 \ hours$ each day and the cost of one electrical unit is $6 \ Rs.$?

The coefficient of performance of a refrigerator working at a temperature of $27^{\circ} C$ is $5$. Find the temperature inside the refrigerator. (in $K$)

$A$ Carnot's engine works as a refrigerator between $250\, K$ and $300\, K$. It receives $500\, cal$ heat from the reservoir at the lower temperature. The amount of work done in each cycle to operate the refrigerator is ..... $J$

$A$ refrigerator consumes an average $35 \ W$ power to operate between temperatures $-10^{\circ}C$ and $25^{\circ}C$. If there is no loss of energy,how much average heat per second does it transfer? (in $J/s$)