Please answer true or false for the following question: a) An instrument with a variable interest rate is commonly tied to an index such as the prime rate. b) During the life of a long-term loan, the principal gets paid down first leaving payments with more interest at the end. c) The Tax Cut and Jobs Act changed the corporate income tax rate to a flat 15%. d) Cash balances at the end of a month is always representative of a company's cash balance during the month e) The study period should only be set by company policy