1. MacGuffins have a demand function of Q^D= 70 - Pand a supply function of Q^S= 2P + 10. Determine the price for a supplied quantity is 0.
2. Let the demand for good X beQ_X= 5 - 3P_X+ 6P_Y+ 0.02I + 0.3A_X.If P_X= 8, P_Y= 4, I = 30,000, A_X= 2,000, what is the cross-price elasticity of demand for Good X and Good Y? the question belongs to L2.3so it has not been covered yet,just enterthe answer:0.0199.
3. Use this demand function to answer the following questions:

Q^D_X= 50 - 0.8P_X+ 5P_Y+ 0.007M. At P_X= $20, P_Y= 10, and M = 50,000, what is Q^D_X?