can we go over question 1. i feel like both b and c are correct and don't really know the difference between the two.

Here's the question:

If a user's browser doesn't support javascript, a site using the jQuery UI
    A. will be broken and unusable
    B. will be able to fall back to HTML primitives
    C. should use progressive enhancement instead
    D. none of the above

The jQuery UI already uses progressive enhancement, so the user's browser doesn't use progressive enhancement instead. It's not switching to a different solution: the jQuery UI solution "gracefully degrades."

The word "instead" is the key.

Can you talk about ARIA in more details?

Sure. Suppose you want to have a DIV or an IMG that is clickable. Well, they can't get focus, so we can't use the keyboard instead. Unless you mark them as such using ARIA.

It's better just to use BUTTON or A instead of ARIA. So, ARIA is mostly unnecessary.

Can you explain a bit more about what regular expressions are and if they are only relevant towards form validation?

Sure. I apologize for not providing a better reading.

Regular expressions use a special language for describing strings or patterns of characters. These turn out to be really useful for searching, parsing and the like.

most of the time, you don't need the really powerful parts of the language, but sometimes you do.

Eg. if I'm searching the password database for "Sally" I can do:

grep Sally /etc/passwd

But if I'm searching for the CS 204 account, I can do:

grep "^cs204" /etc/passwd

I have no questions! / None, these readings were very easy to follow :)

I'm glad it worked for you!