The city of Tulsa conducts a traffic flow study at the area bounded by Clay Ave., Webste...

The city of Tulsa conducts a traffic flow study at the area bounded by Clay Ave., Webster Ave., and 4th and 5th Streets. All of the streets are one-way streets. The map shows the number of vehicles entering or leaving the area. For example, 800 vehicles per hour enter intersection A from Clay Ave., and 300 vehicles per hour leave intersection D on Webster Ave. You are to find the traffic flow on the four blocks between intersections A, B, C, and D.

(a) Set up a system of equations that represents the relationships between the given traffic flows and the traffic between intersection A and B, B and C, C and D, and D and A.

(b) Solve the system.

(c) Determine the maximum and minimum number of vehicles per hour on each street in the block ABCD.

(d) What is the largest traffic flow on Clay Ave. so that the traffic flow on each of the other three streets is nonnegative? How do you interpret this value?