The town of Springfield has two types of residents: high- and low- types. There are 5 of each type in Springfield. The high-type residents place a high value on firefighters and have the following marginal benefit from firefighters where XT is the total number of firefighters in Springfield: MBH = 20 + XT The low-type residents place a low value on firefighters and have the following marginal benet from firefighters: MBL = 20 + 2XT The town currently funds its fire department solely from the individual contributions of these residents. Assume the marginal cost of firefighters: M C = 20 + 3XT where 20 represents each firefighter's wages and 3XT represents training costs. (a) Solve for and graph the total marginal benefit for firefighters among Springfield residents. Be sure to label intercepts and any kink points in this relationship