For many years, college costs (including tuition, fees, and room and board) increases have been higher than the inflation rate, averaging 5% to 8% per year. According to the College Board's Trends in College Pricing, the average total costs at present in dollars is $19,500 for students attending in-state four-year public colleges and universities and $41,000 for students at four-year private colleges and universities. Assume an additional $5,000 per year for textbooks, supplies, transportation, and other expenses. Using a 7% per year inflation rate, how much can a sophomore high-school student expect to spend on in-state tuition, fees, and room and board for the freshman year (3 years from now) at a four-year public university?
A sophomore high-school student is expected to spend $ for the freshman year.

Areal estate agent is considering changing her cell 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 $.42 a minute for daytime calls and $.17 a minute for evening calls. plan b has a charge of $.52 a minute for daytime calls and $.15 a minute for evening calls. plan c has a flat rate of $80 with 275 minutes of calls allowed per month and a charge of $.38 per minute beyond that, day or evening.a. determine the total charge under each plan for this case: 150 minutes of day calls and 70 minutes of evening calls in a month. (do not round intermediate calculations. round your answer to 2 decimal places. omit the "$" sign in your response.)c. if the agent will use the service for daytime calls, over what range of call minutes will each plan be optimal? (round each answer to the nearest whole number.include the indifference point itself in each answer.)d. suppose that the agent expects both daytime and evening calls. at what point (i.e., percentage of total call minutes used for daytime calls) would she be indifferent between plans a and b?