Reading external variables

[FONT=Arial][SIZE=2]I have a question:

I have a page in which the user will click on a watch video buton. This button is controlled via JavaScript (another programmer did this). He asked if it would be possible to have a swf with two buttons on it (on the same page where the JavaScrpt is): Low and high. The user should be able to choose one of the the two types of video (low or high resolution).

The problem:
1 - The javaScript is sending the two variables with the low and high values. How my swf can access these variables.

2 - On youtube.com, as I noticed, when you click on a link for a video, i.e: [COLOR=#003366]http://www.youtube.com/watch?v=65N_1eSkKWg[/COLOR], it seems to me that the swf read that address and reacts acordingly.

3 - What kind o method inflash should I look into in order to start my programming?
loadVars() or something like that?

Thanks.
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