Well i'll be a little helpful, since its my first post. These questions can be answered if you take a little time to study the periodic table, and consider some of the bonding going on. For instance, the first question you ask regarding the valency of bonding for SO2, how many bonds are there between a sulphur and one oxygen? That sort of thing.
Give it a little thought, go through your notes and look in some books, and get back with what you think the answers may be.
Good luck,
Matt
(p.s you seem new to chemistry if this stuff is a little difficult to you? Dont worry, I couldnt get anything at first!)