About black body radiation, which one of the following is a WRONG statement?

In thermodynamic isobaric process

A monoatomic gas is stored in a thermally insulated container and the gas is suddenly compressed to $\left(\dfrac{1}{8}\right)^{th}$ of its initial volume. The ratio of final pressure to initial pressure is

The average force applied on the walls of a closed container depends on temperature (T) as (T is the temperature of an ideal gas)