Let a demand curve be given by Q : 30 X Y 6 x PQ + 6 X PZ, where Q is the quantity demanded, Y is income, PQ is the own price, and P2 is the price of another good, Z. If Y22 and PQ : P322, how much is demanded? Is Q a normal good? How do you know? Calculate the income elasticity of a 10 percent increase in Y if Y22 and PQ : P222 initially