A sales tax of $1 per unit of output is placed on one firm whose current equilibrium price is $5 and current equilibrium quantity is 100 units. If you know that the elasticity of demand is -1 and the elasticity of supply is (infinity), then after the tax: a. pb=6, ps=5, and QT=unknown but less than 100
b. pb=4, ps=5, and QT=unknown but less than 100
c. pb=6, ps=5, and QT=100
d. pb=4, ps=5, and QT=100

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?