Three multiple choice questions attached, help please?

Question

anonymous · Answer

attachment

anonymous · Answer

Hi @danielamarques - please don't post questions like this on OpenStudy. We are here to help you understand your problems, not simply provide you answers. In the future, please post your questions by writing them out, and attempting to learn how to solve them, thank you.

Feel free to contact us at abuse@openstudy.com if you have any questions, thank you.

anonymous · Answer

Look @cshalvey , I didn't ask for answers I clearly said "help please" I would have attempted to learn how to solve them and wrote them out but I don't know how to with all those symbols. But now I'll never learn since you closed my question.

zarkon · Answer

then why don't you post the first one on your list in a new post?

anonymous · Answer

Hi @danielamarques - fair point, and I'll try and make sure you get the help you need. In terms of writing out the equations, I completely understand your point, and we can see what we can do about helping you with that.

zarkon · Answer

you can always draw it

|dw:1341690179388:dw|

if you cant do this 

$$\sum_{i=1}^{\infty}\left(\frac{1}{2}\right)^{i}$$