A job hunter is interested in whether the employment year (X) at a company is a good indicator for their annual salary (Y in thousands). 10 employees are randomly selected and their employment years and annual salaries are: year 1 2 3 4 5 6 7 8 9 10 salary 64 67 63 66 61 81 85 82 95 90 Assume the random error follows i.i.d. normal distributions. Compute a least square regression line Y = a + 3(X - x) from these data (round to 3 decimal places). 1. the estimate a [ Select ] 2. the estimate [ Select ] 3. the variance of 3 [ Select ] if the true variance of residual is known to be 25