4. A select life aged 51 exact purchases a 3-year endowment assurance with sum assured 20,000. The death benefit is payable at the end of the policy year of death. The interest rate is 4.5% p.a. Mortality is given by q[xt]+t=(4t)1qx for all x and for t=0,1,2 with q51=0.02,q52=0.022 and q53=0.024. (a) Complete the following table (b) Using part (a), compute the expected present value of the benefit. (c) Compute the variance of the present value of the benefit