Welcome to the forums andre1.
I think you haven't read the notices written right on the top of your post. On the forums we don't do homeworks and your post looks like one. The best way that you can make use of these forums is that you show the members that you have put an effort to do your homework and then you ask for help.
And a second thing I'd like to mention is your thread title. Starting your title by using imperatives will severely lower your chance to get answers. Our teachers answer other member's questions on a voluntary basis not because they have to.
So, in a nutshell, as long as you follow a few simple forum rules, it is a good chance that you get your answers.
By the way, be sure that you put full stop at the end of your all sentences.
- For Teachers