a) Compare the costs of the following two electric motors in order to determine which is more economical based on an expected service life of 4 years and a cash discounting rate of 10% per annum. Show all your working. Initial cost Uniform annual maintenance cost Salvage value Motor 1 $9000 $300 $1000 Motor 2 $6500 $750 $100 (6 marks) b) Calculate the fortnightly payments and total interested paid on a 25 year mortgage with an initial loan amount of $300,000, a nominal interest rate of 5% per annum. F=P(1 + i)n A=F