Sonia has $2,400 a month to spend on clothing and food. The price of clothing is $60 and the price of food is $10. The clothing and food pairs in Sonia's choice set include units of clothing and units of food. A) 40; 100 B) 30; 140 C) 20; 120 D) 0; 400

You are the manager of a large crude-oil refinery. as part of the refining process, a certain heat exchanger (operated at high temperatures and with abrasive material flowing through it) must be replaced every year. the replacement and downtime cost in the first year is $165 comma 000. this cost is expected to increase due to inflation at a rate of 7% per year for six years (i.e. until the eoy 7), at which time this particular heat exchanger will no longer be needed. if the company's cost of capital is 15% per year, how much could you afford to spend for a higher quality heat exchanger so that these annual replacement and downtime costs could be eliminated?