Your firm is considering the purchase of a new office phone system. You can either pay $31,500 now, or $1,050 per month for 35 months. a. Suppose your firm currently borrows at a rate of 5% per year (APR with monthly compounding). Which payment plan is more attractive? b. Suppose your firm currently borrows at a rate of 20% per year (APR with monthly compounding). Which payment plan would be more attractive in this case