Answer:
The pressure must have increased in the process
Explanation:
The State Equation for gasses reads:
where P is the gas' pressure, V its volume, n the number of moles of gas, R the gas constant and T the temperature in degrees Kelvin.
If the temperature of the gas doesn't change in the described process, the right hand side of the equation stays the same. If that is the case, given that when the Volume of the gas diminishes from 75 liters to 50 liters, then the pressure must have increased to keep that product "P * V" constant:
So the pressure must have gone up to 450 kilopascals.