4. The following table lists the annual incomes (in thousands of dollars) and amounts of life insurance (in thousands of dollars) of life insurance policies for six person. Annual income 45 52 24 36 60 18 Life insurance 250 300 100 150 500 75 a) Fit a least square line y = a + bx with annual income as an independent variable and amount of life insurance policy as a dependent variable, b) Determine the estimated value of life insurance of a person with an annual income $50,000