1. Briefly explain the use of graphs as a way to represent economic relationships. What is an inverse relationship? How does it graph?

What is a direct relationship? How does it graph? Graph and explain the relationships you would expect to find between

(a) the number of centimetres of rainfall per month and the sale of umbrellas,

(b) the amount of tuition and the level of enrolment at a college or university, and

(c) the popularity of a music artist and the price of her concert tickets.

In each case cite and explain how variables other than those specifically mentioned might upset the expected relationship. Is your graph in part

b, above, consistent with the fact that, historically, enrolments and tuition have both increased? If not, explain any difference.