1. The demand function for a cola-type soft drink in general is Q= 20 - 2P, where Q stands for quantity and P stands for price.

a. Calculate point elasticities at prices of 5 and 9. Is the demand curve elastic or inelastic at these points?

b. Calculate arc elasticity at the interval between P = 5 and P =6.

c. At which price would a change in price and quantity result in approximately no change in total revenue? Why?

2. ABC Sports, a store that sells various types of sports clothing and other sports items, is planning to introduce a new design of Arizona Diamondbacks' baseball caps.  A consultant has estimated the demand curve to be

Q =2,000 - 100P

where Q is cap sales and P is price.

a. How many caps could ABC sell at $6 each?

b. How much would the price have to be to sell 1,800 caps?

c. Suppose ABC were to use the caps as a promotion. How many caps could ABC give away free?

3. Mr. Smith has the following demand equation for a certain product: Q = 30 - 2P.

a. At a price of $7, what is the point elasticity?

b. Between prices of $5 and $6, what is the arc elasticity?

c. If the market is made up of 100 individuals with demand curves identical to Mr. Smith's, what will be the point and arc elasticity for the conditions specified in parts a and b?