After working for 25 years as personal fitness trainers while raising their​ kids, three sisters cashed in a total of ​$80 comma 000 in bonds and decided to open a​ small, neighborhood fitness center. they spent the ​$80 comma 000 on exercise​ equipment, advertising, computer​ equipment, and other furnishings for the business. for the next 3​ years, they took in ​$150 comma 000 in revenue each​ year, paid themselves ​$35 comma 000 annually​ each, and rented a space in a strip mall for ​$22 comma 000 per year. before the​ investment, their ​$80 comma 000 in bonds were earning interest at a rate of 15 percent. are they now earning economic​ profits? explain​ your answer.

In the fall, jay thompson decided to live in a university dormitory. he signed a dorm contract under which he was obligated to pay the room rent for the full college year. one clause stated that if he moved out during the year, he could sell his dorm contract to another student who would move into the dormitory as his replacement. the dorm cost was $5000 for the two semesters, which jay had already paid a month after he moved into the dorm, he decided he would prefer to live in an apartment. that week, after some searching for a replacement to fulfill his dorm contract, jay had two offers. one student offered to move in immediately and to pay jay $300 per month for the eight remaining months of the school year. a second student offered to move in the second semester and pay $2500 to jay. jay estimates his food cost per month is $500 if he lives in the dorm and $450 if he lives in an apartment with three other students. his share of the apartment rent and utilities will be $404 per month. assume each semester is 4.5 months long. disregard the small differences in the timing of the disbursements or receipts. what is the cost of the cheapest alternative?