Computing aggregate quantity demanded

Question

1. Danielle's demand curve for product is Q_D(p) = 12 - p. Current price of product is $6.
a. Calculate Danielle's consumer surplus for this price.

b. Calculate the point price elasticity for this price.

c. If price of product increased, would Danielle's total expenditure on product increase or decrease? How can you tell?

2. One consumer's demand curve for some product is q₁(p) = 16 - p. Another consumer's demand curve is q₂(p) = 24 - 2p.

a. Compute the aggregate quantity demanded when the price is $14?

b. Compute aggregate quantity demanded when the price is $10?

c. Draw demand curve for each consumer and aggregate demand curve. Give values for each price and quantity intercept.