Suppose that you have $100 today and expect to receive $100 one year from today. Your money market account pays an annual interest rate of 25%, and you may borrow money at that interest rate. Consider the budget constraint between "spending today" on the horizontal axis and "spending a year from today" on the vertical axis. What is the slope of this budget constraint?

A) −0.75
B) −1.00
C) −1.25
D) −2.25

Your next-door neighbor has a beautiful rose garden, but you are allergic to roses and cannot use your yard because of the rose pollen that drifts into your yard. In this case, the rose garden is an example of a

A) public good.
B) good that imposes an external cost.
C) good that provides an external benefit.
D) Pareto good.