The Marshallian demand for good x and y is given by x (Px, Py, M) and y (Px, Py, M),
respectively. Calculate the income elasticity of good x. Is good x income elastic? Unitary?
inelastic?
A. 1, income elastic
B. -1, income unitary
C. 1, income inelastic
D. -1, income is perfectly inelastic