Review Questions and Exercises 22. 25 characters or symbols mark the beginning or end of programming state ments, or separate items in a list. 23The rules that must be followed when constructing a program are called 24. Ain)is a named storage location. 25. A variable must be before it can be used in a program. 26.The three primary activities of a program are and 27 28. 29. A(n) is information a program gathers from the outside world. is information a program sends to the outside world is a diagram that graphically illustrates the structure of a program Algorithm Workbench Draw hierarchy charts or flowcharts that depict the programs described below. (See Appendix C for instructions on creating flowcharts.) 30. Available Credit The following steps should be followed in a program that calculates a customer's available credit: 1. Display the message "Enter the customer's maximum credit. 2. Wait for the user to enter the customer's maximum credit. 3. Display the message "Enter the amount of credit used by the customer 4. Wait for the user to enter the customer's credit used S. Subtract the used credit from the maximum credit to get the customer's available credit. 6. Display a message that shows the customer's available credit Design a hierarchy chart or flowchart for a program that calculates the total of a retail - The retail price of the item being purchased 31. Sales Tax sale. The program should ask the user for: - The sales tax rate program should calculate and display: - The sales tax for the purchase - The total of the sale Design a hierarchy chart or flowchart for a program that calculates the current balance in a savings account. The program must ask the user for 32. Account Balance - The starting balance - The total dollar amount of deposits made - The total dollar amount of withdrawals made - The monthly interest rate ng unt hd dliyl on the srem. Onc the pogram calchb