For society, more money means more wealth

Product differentiation allows the firm to

a. raise price and lower quantity demanded b. raise price without suffering a substantial loss of sales c. shift the market demand curve to the left d. shift the market supply curve to the left e. decrease barriers to entry

The price of a new textbook increases from $75 to $90 while the price of used copies of the textbook increases from $50 to $65. Other things equal, we would expect to observe

A) the quantity demanded of the used textbook to increase while the quantity demanded of the new textbook to fall. B) the quantity demanded of both to fall. C) the demand for the new textbook to increase while the demand for the used textbook to decrease. D) the quantity demanded of the used textbook to decrease and the quantity demanded of the new textbook to increase.