Suppose two children push horizontally, but in exactly opposite directions, on a third child in a wagon. The first child exerts a force of 75.0 N, the second a force of 94.0 N, friction is 12.0 N, and the mass of the third child plus wagon is 30.0 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.) the children outside the wagon the wagon the child in the wagon (b) Draw a free body diagram, including the weight and all other forces acting on the system. (Do this on paper. Your instructor may ask you to turn in this diagram.) (c) Calculate the acceleration. m/s2 (d) What would the acceleration be if friction is 19.0 N