php and html coding

[login to view URL] a Guest book that stores visitor first name, last name, email address/username and comments (after validating through regular expression) in a text file. Include functionality that allows users to view the guest book and prevents the same user name from being entered twice. If the guest book is empty, a message should be displayed, nothing to display. Also, include code that sorts ands display the guest book by first name. q2. Create a web application that simulates a soft-drink vending machine. The application should let the user select one of the following soft drinks: • Cola ($2.00 each) • Root bear ($2.00 each) • Lemon lime soda( $1.00 each) • Grape Soda ($1.50 each) • Cream Soda ($1.50 each) Options should display image as well as price for each drink. When the application starts, the vending machine will have 20 of each type of soft drink. Each time the user selects a drink, the application should subtract 1 from the quantity of the selected drink. It should also update and display the total amount of sales. If the user selects a drink that is sold out, a message should be displayed indicating so.