An investment in a truck is expected to have initial cost N in the year 2020, annual net benefits that start at 20,000$/yr in 2019 and grow at 2%/yr compounded until 2130 and a resale value of N2 when sold in 2030. N(240, 30) and N(160, 40) are normally and independently distributed, with their means and standard deviations given in thousands of $. The interest rate is 5%/yr. Find: a. (7%) The expected net present value of this investment. b. (7%) The probability that this investment will be profitable.