This is an ideal gas law question. Use the equation PV =nRT.
P(0.75) = (2.150)(0.08206)(273+57)
P = 77.63atm
The answer needs to be in kPa and theres 101.325kpa per 1atm, so
77.63*101.325 = 7865.73 kPa
If youre supposed to have 3 significant figures, then 7870kPa