(Business: check ISBN-10) An ISBN-10 (International Standard Book Number) consists of 10 digits: The last digit, is a checksum, which is calculated from the other nine digits using the following formula: If the checksum is 10, the last digit is denoted as X, according to the ISBN convention. Write a program that prompts the user to enter the first 9 digits as a string and displays the 10-digit ISBN (including leading zeros). Your program should read the input as a string. Here are sample runs: |

Text: ISBN Codes. Every book has an International Standard Book Number (ISBN) code. This is a 10-digit code indicating the book's publisher and title. The tenth digit is a check digit satisfying (d1, d2, ..., d10) · (10, 9, ..., 1) ≡ 0 (mod 11). One problem is that d10 might have to be a 10 to make the inner product zero; in this case, 11 digits would be needed to make this scheme work. Therefore, the character X is used for the eleventh digit. So ISBN 3-540-96035-X is a valid ISBN code. (a)