Two students, Cindy and Xavier, are discussing labour-leisure choice. Cindy says that if Kimberley has upward-sloping labour supply curve, then leisure must be a normal good for her. If, on the other hand, she is on the backward-bending part of her labour supply curve, then leisure must be an inferior good for her. Xavier disagrees: "Normal and inferior goods are about income changes, not wage changes. Therefore, we do not have enough information: for Kimberly, leisure could be an inferior or normal good in either of these cases."

Do you agree or disagree? Carefully explain your point of view. Support your argument with graphs of income, substitution and total effects (please put leisure on the horizontal axis and the other goods on the vertical axis).

Please assume that Kimberley's preferences over leisure and other goods are strictly convex and satisfy "more is better" assumption.