For each of the following, state whether the statement, which describes changes in the tangerine market, is true, false, or uncertain. Explain your answer using graphs and the model of labor and capital markets.

a. As consumer income increases and wages fall, price will rapidly fall in response to an increase in the quantity of tangerines sold.

b. The price of tangerines falls and the tax rate on citrus fruits also decreases. This results in the quantity of tangerines demanded decreasing and price rising.

c. During an unusually cold December, the month when most tangerine varieties ripen, the quantity demanded decreases and the price falls. At the same time, the price of canning machinery (a complementary good) rises.