turning moment diagram of a four - stroke engine

Question

A simplified turning moment diagram of a four - stroke engine is shown in the given figure. If the mean torque T_m  <!--[if gte mso 9]> <![endif]-->will be (assuming negative torque demand is negligible 

 

(a) 80 Nm          (b) 120 Nm     (c) 60 Nm       (d) 40 Nm