Verified answer

Use the formula pv=nrt. Since you want to find p (pressure) change that into p= (nrt)/v.

N= number of moles. (.255)

R= the constant (.08206 atm) (this is universal)

T= temperature in kelvins. So 28 degrees converted into kelvins, which I think you just add 270 but you may want to check me on that.

Multiple those three together and then divide by

V= volume. In liters. So change 748 ml to liters. (.748 liters)

There you have it!