The net torque exerted by the children on the branch of the tree is 1382 N-m.
The torque exert by the kids is calculated as
T= 45.6*9.8*1.28*cos27.5°+36*9.8*(2.25-1.28)cos27.5°
T=1382 N-m
Hence, The net torque exerted by the children on the branch of the tree is 1382 N-m.