You own a clothing store in Tacoma, Washington. One of the items you sell are sweaters with the logo "Make Tacoma Stink Again" to support the campaign to reopen the paper mill. You have many one-day...

You own a clothing store in Tacoma, Washington. One of the items you sell are sweaters with the logo "Make Tacoma Stink Again" to support the campaign to reopen the paper mill. You have many one-day sales and keep track six times of the size of the discount (in dollars) and the number of sweaters sold. Your data for the six sales is:

Sale number 1 2 3 4 5 6

Discount (in dollars) 4 4 6 14 4 4

Swearers Sold 6 10 4 26 16 10

If you are predicting the number of sweaters sold based on the size of the discount, what is the y-intercept, a, of the regression line?