George Caloz & Frres, located in Grenchen, Switzerland, makes luxury custom watches in small lots. One of the companys products, a platinum diving watch, goes through an etching process. The company has recorded etching costs as follows over the last six weeks:

Week	Units			Total Etching Cost
1		14			$	27
2		11				20
3		16				30
4		10				20
5		12				25
6		15				28
		78			$	150

For planning purposes, management would like to know the variable etching cost per unit and the total fixed etching cost per week.

Required:

1. Use Excel to prepare a scatter-graph that puts labor-hours on the X-axis and overhead expenses on the Y-axis. Add a trend line, display the cost formula, and R² value.

2-a. From your results in part 1 above, Using the least-squares regression method, estimate the variable etching cost per unit and the total fixed etching cost per week.

2-b. From your results in part 2a above, express these estimates in the form Y = a + bX.