Adriana Corporation manufactures football equipment. In planning for next year, the managers want to understand the relation between activity and overhead costs. Discussions with the plant supervisor suggest that overhead seems to vary with labor-hours, machine-hours, or both. The following data were collected from last year's operations.

Month	Labor-Hours			Machine-Hours			Overhead Costs
1		730			1,357		$	102,618
2		715			1,414			103,892
3		680			1,519			109,993
4		745			1,452			108,372
5		785			1,586			116,258
6		750			1,580			114,487
7		730			1,388			107,084
8		730			1,301			102,104
9		720			1,461			106,382
10		795			1,537			113,000
11		675			1,298			101,749
12		710			1,608			114,304

Required:

a. Use the high-low method to estimate the fixed and variable portions of overhead costs based on machine-hours.

b. Managers expect the plant to operate at a monthly average of 1,500 machine-hours next year. What are the estimated monthly overhead costs, assuming no inflation?