The following table gives the experience (in years) and the number of computers sold during the previous three months by seven salespersons.

Experience ( years)	4	12	9	6	10	16	7
Computer sold {unit)	19	42	28	31	39	35	21

1. Find the suitable least squares regression line.
2. Give a brief interpretation of the values of the Y-intercept and slope calculated in the previous part.
3. Calculate the correlation coefficient and the determinant coefficient. Explain what they mean.
4. Predict the number of computers sold during the past three months by salespersons with eleven years experience.