Indicate whether the following statements are true, false, or uncertain. If false or uncertain, explain why.
a. The price of a watch increases by 10%, and you spend a larger fraction of your income on it. The watch is a Giffen good.
b. Due to a flood, corn prices and soybean prices increase. If corn and soybeans are substitutes, the quantity of corn demanded falls.
c. Goods 1 and 2 are substitutes, and goods 2 and 3 are substitutes. This must mean that goods 1 and 3 are substitutes.