The demand for your product has been estimated to be

Qx =8000 - 5Px- 3 Py+ Pz +.1M

The relevant price and income data are as follows:

Px (Price of x)= 10

Py (Price of y) = 20

Pz (Price of z) =60

M (Income) = $50,000

a. Which goods are substitutes for X? Which are complements?

b. Is X an inferior or a normal good?

c. How much X will be purchased?

d. How will the demand curve change if M falls to 35,000?