The government imposes an excise tax on the sale of all college textbooks. Before the tax was imposed 1 million textbooks...

The government imposes an excise tax on the sale of all college textbooks.

Before the tax was imposed 1 million textbooks were sold every year at price

of $50. After the tax is imposed 600, 000 books are sold yearly; students pay

$55 per book, while publishers receive $30 per book.