Answer
$1.5\times10^{5}Nm$
Work Step by Step
$\omega=\omega_{0}+at$, where a is angular acceleration.
$2=0+a12$
$a=\frac{1}{6}rad/s^{2}$
Now, $I=\frac{1}{2}MR^{2}=\frac{1}{2}\times2000\times30^{2}=900000kgm^{2}$
Torque = $900000\times\frac{1}{6}=1.5\times10^{5}Nm$