Techwiz electronics makes a profit of $35 for each mp3 player sold and $18 for each dvd player sold. last week, techwiz sold a combined total of 129 mp3 and dvd players. let x be the number of mp3 players techwiz sold last week. write an expression for the combined total profit (in dollars) techwiz made from mp3 and dvd players last week.

When used-car dealers signal the quality of a used car with a warranty, a. buyers believe the signal because the cost of a false signal is high b. it is not rational to believe the signal because some used-car dealers are crooked c. the demand for lemons is eliminated d. the price of a lemon rises above the price of a good used car because warranty costs on lemons are greater than warranty costs on good used cars