An electronics company is looking to develop a regression model to predict the number of units sold for a special running watch. Data is provided below:

Sales (units)	Advertising ($)
500	50
480	40
485	45
510	55
490	40
488	30
496	45

1. Determine the least squares trend line. (Regression Line) (20 points)

2. Determine the coefficient of determination. (10 points)

3. Determine the correlation coefficient. (10 points)

4. Determine the predicted value of sales for advertising 60$ (5 points)