[填空题]
In an internal combust-m63u5nkzvpiy xhb,0 q 1j;0k2m3 ;osyoxc9t qnz7wqion engine, air at atmospheric pressure and a temperature of about 20c;owx 7;9j 3myqns qk20oz1qt$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm. $^{\circ} $ C