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		16			$	26
2		11			$	24
3		17			$	29
4		9			$	23
5		13			$	25
6		16			$	28
		82			$	155

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.