Statistics homework help

I just want to know how to do the (a).I am fine with the rest.Problem !’The safety system of a pressurized water reactor ( PWR ) is equipped with two accumulators con -taining pressurized Nitrogen gas . Each accumulator has a volume of 9.5 m’ and contains Nitro -gen gas at a pressure of 6.5 MP a and a temperature of 80 C. Due to a leak in one of theaccumulators , the gas starts flowing out through a 0. 6 cm _ opening . Calculate :"( a) the initial pressure of Nitrogen in each accumulator ,( 6 ) the temperature , pressure and gas mass in the leaking accumulator after 4 min from thebeginning of the leak .( C ) the time required to remove 40% of the initial mass of the gas from the leaking accumulatorand the corresponding final gas pressure .NOTE : Nitrogen can be treated as ideal gas and the flow is isentropic .