you have two identical 25-kg crates. initially the crates are sitting on the floor of a frictionless surface. the crates are connected together by a rope, whos mass we can ignore. a second rope is used to pull the system by attaching itself the the front of one of the 25-kg crates. we can ignore the mass of this rope as well. the whole system moves to the right, with an acceleration of 4 m/s^2. determine the tension of both ropes.