what would the temperature inside the pressure cooker beef the vapor pressure of water inside the cooker was 3.08 atm

Answer 1

Can't you use the Clausius-Clapeyron equation.
ln(p2/p1) = dHvap(1/T1-1/T2)/R

You have p1 = 1 atm with T1 = 373 and you have p2 and listed. Solved for T2 in K. Convert to C is needed.