Here are a couple of my homework problems that I need some help with. I don't know where to even start. Would someone please be kind enough as to help?

Problem 1. http://i42.tinypic.com/2ikusjn.jpg

I need to find measures of angles

(a) BAC

(b) ABD

(c) DBC

I was also suppose to find measure of arc AD and I found it to be 56, is that correct?

Problem 2. http://i43.tinypic.com/1fu0xi.jpg

Solve for x and y.

I found x = 50 but i have no idea where to start with y.

Problem 3. http://i44.tinypic.com/34zbubm.jpg

Solve for z.

I guess my biggest problem is i don't know the relation between the different inscribed angles. Any help would be greatly appreciated! Thank you very much in advance.