By what factor does the average velocity of a gaseous molecule increase when the temperature (in Kelvin) is doubled ?

The pressure exerted by 6.0 g of methane gas in a 0.03 m³ vessel at 129^oC is (Atomic masses : C = 12.01, H = 1.01 and R = 8.314 J K^$$-$$1 mol^$$-$$1 )

The energy absorbed by each molecule (A₂) of a substance is 4.4 $$ \times $$ 10^$$-$$19 J and bond energy per molecule is 4.0 $$ \times $$ 10^$$-$$19 J. The kinetic energy of the molecule per atom will be

Volume occupied by one molecule of water (density = 1 g cm^$$-$$3) is