Astore owner paid $15 for a book she marked up the price of the the book by 40% to determine its selling price part a what is the selling price of the book? part b a customer buys a different book that has an original selling price of $38 the book is discounted 25% the costumer must pay 6% sales tax on the discounted price of the book .what is the total amount the customer must pay for the discounted book