Captcha like verification script

Need a script that functions like a captcha verification. Does not need encryption. * reads a random line from a file. Lets say that file is called "[login to view URL]", the format of the file would be: URL, Question, Answer URL, Question, Answer, Popup Url URL, Question, Answer, Popup Url URL, Question, Answer, Popup Url * The script would pick a random line from that file, give the user the question and have the Popup Url open in a new window. * The answer would be held in a variable and passed using the php session feature. * Need detailed instructions on how to add and format on webpage. This project needs to be completed rather quickly. As soon as I can find someone qualified within the specified rate I will be closing this to bidding. So please act fast. If you have any other questions, please contact me.