Hello, please kindly help me with the chemistry exercises? Thanks a lot!

8/ This relation binds the same quantity of gas in 2 different states.

P1*V1 / T1 = P2 * V2 / T2 a) From the ideal gas law, find this relation b) A certain quantity of gas occupies a volume of 67.2 L at 0 ^oC and 760 mmHg. What is the volume occupied by this gas at 20 ^oCand 700 mmHg?

9/ what is the pressure exerted by 48g of oxygen in a volume of 36 liters s 127 ^oC