Suppose Two children push honizonealy, but. in exactly opponite directions, on a third children in a wagon. The first child exerts a force of 75.0 N, the second a force of 90.0 N, friction is 12.0 N, and the mass of the third child plus wagon is 28.0 kg. (a) what is the system of interest if the acceleration of the child in the wagon is to be calculated? (Select all that apply) 1.the children outside the wagon 2.the children in the wagon 3.the wagon (b) draw a free body diagram, including the weight and all other forces acting on the system (c) calculate the acceleration in m/s^2 (d) what would the acceleration be if friction is 15.0 N