Compiling & Creating Mathematical Questions + Solutions (Statististics)

Hi, I need somebody to compile or create a list of Questions and Answers (with step-by-step) workings of University Mathematical topics. I need at least 20 -30 questions for each SUB-topics, covering all possible questions to be tested in the examinations. Questions must have a high level of difficulty - for 1st year's University students The topics to be covered are: Probability, Random Variations and Probability Distributions Detailed SUB-topics of main Topics will be PMed. You are allowed to find sources from books, internet and others. I will pick the lowest bid with the most number of Questions & Answers compiled. This will be long term for future topics.