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	9	$ 25
2	6	20
3	11	30
4	5	21
5	7	21
6	14	32
	52	$ 149

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

2-a. Using the least-squares regression method, estimate the variable etching cost per unit and the total fixed etching cost per week.

2-b. Express these estimates in the form Y = a + bX.