4. a. Jason started working on construction projects, earning a handsome salary per month. He plans to save money from his monthly salary to deposit $300,000 at the end of each year in the bank. As the bank provides him with a 4% Interest rate, how much he will accumulate by the end of 6 years? b. Maintenance costs for a concrete mixer increase by $2,000 per year over the 10- year life of the equipment. The initial maintenance is $3,000. Using an interest rate of 10% compounded annually, determine the present worth equivalent to maintenance costs