in the following two panels, the demand for good x shifts due to a change in income (panel A) and a change in the price of a related good Y (panel B). holding the price of good X constant at $50, calculate the following elasticities: a. panel A shows how the demand for X shifts when income increases from $30,000 to $34,000. use the information in Panel A to calculate the income elasticity of demand for X. is good X normal of inferior?