To answer your poll, which I truly don't understand why you created, no - you aren't specific enough. What have you tried? Where exactly are you stuck? It seems the math of the first part should be straightforward...have you written any code? We aren't a homework service - the more effort you make to create a concise and answerable question, the higher the chances your question will be answers. The second part makes no sense - the bottom of a cylinder? Where? What cylinder? Does this mean you need to draw a cylinder in a user interface?