The volume of given mass of a gas is increased by $7 \%$ at constant temperature. The pressure should be increased by

A monoatomic ideal gas is compressed adiabatically to $\left(\frac{1}{27}\right)$ of its initial volume. If initial temperature of the gas is ' T ' K and final temperature is ' xT ' K , the value of ' x ' is

Select the correct statement.

A polyatomic gas at pressure P , having volume ' $V$ ' expands isothermally to a volume ' 3 V ' and then adiabatically to a volume ' 24 V '. The final pressure of gas is (for moderate temperature changes)