Suppose that one U.S. dollar can purchase 1.10 Canadian dollars. Which of the following options represents an example of the law of one price?
1) A shirt costs $20 in the U.S. and $22 in Canada.
2) A gallon of milk costs $3 in the U.S. and $3.30 in Canada.
3) A movie ticket costs $10 in the U.S. and $11 in Canada.
4) A loaf of bread costs $2 in the U.S. and $2.20 in Canada.