3. Julia is an amateur singer who wants to make her own music compact discs (CDs) and send copies to recording companies. A local store sells recordable CDs at a price of $10 for a packet of fifty. Julia's demand for recordable CDs is: Q = 12 - 0.4P , or and inverse demand of P = 30 - 2.5Q, where Q = number of packets of fifty CDs per year, and P = price per packet, in dollars. (Note: Julia's demand curve remains the same for this entire problem, which is what you should always assume for any multi-part problem unless stated otherwise.)

(a) (4 points) How many packets of CDs will Julia buy?

(b) (4 points) What is Julia's consumer surplus at the quantity found in part (a)?

(c) (4 points) What is the price elasticity of demand at the quantity found in part (a)?

(d) (18 points) Julia discovered that her local Discount Club sells recordable CDs at a price of $10 for the first packet of fifty and then the price drops to only $5 for all remaining packets of fifty purchased. She must also pay a one-time (non-refundable) up-front membership fee of $50 to join the Discount Club. Answer the following:

• (a) (8 points) How many packets of CDs will Julia buy
• (b) (5 points) What is her consumer surplus?
• (c) (3 points) Should she purchase from her local store or the Discount Club? Why?