During rush hours, substantial traffic congestion is encountered at the intersections shown in the 300 in 1800 out figure. (The arrows indicate one-way streets.) The city wishes to improve the signals at these corners to speed the flow of traffic. The traffic engineers first gather data. As the figure shows, 500 cars per hour come down M Street to intersection A, and 300 cars per hour come down 10th Street to M St. intersection A. x, of these cars leave A on M Street, and x, cars leave A on 10th Street. The number 500 in B 300 out of cars entering A must equal the number leaving, so that x, + x = 500 +300-800. Similarly, for intersection B, X, + X, = 800+ 300 = 1100. Complete parts (a) through (e) below. N SL 200 out C 400 in 300 out 400 in 10th St. 11th St. (a) Enter two equations representing the traffic entering and leaving intersections C and D. D: (Type equations.)