Consider the following pairs of goods. For which of the two goods would you expect the demand to be more price elastic? Why? (In order to receive full credit for your answer, be sure to provide explanation for your answer.)

(a) water or diamonds

(b) insulin or nasal decongestant spray

(c) food in general or breakfast cereal

(d) gasoline over the course of a week or gasoline over the course of a year

(e) personal computers or IBM personal computers