A real estate agent is considering changing her land line phone plan. There are three plans to choose from, all of which involve a monthly service charge of $20. Plan A has a cost of $.45 a minute for daytime calls and $20 a minute for evening calls. Plan B has a charge of $.55 a minute for daytime calls and $15 a minute for evening calls. Plan C has a flat rate of $80 with 200 minutes of calls: allowed per month and a charge of $.40 per minute beyond that, day or evening. a. Oetermine the total charge under each plan for this case. 120 minutes of day calls and 40 minutes of evening calls in a mionth. Answer is complete but not entirely correct. answer to the nearest whole number.) Answer is complete but not entirely correct. c. Suppose that the agent expects both daytime and evening colls. At what point (l.e. percentage of total call minutes used for daytime calls) would she be indifferent between plans A and B ? (Do not round intermediate calculations. Enter your answer as a percentage rounded to 2 decimal places. Omit the "\%, hign in your response.) Answer is complete but not entirely correct