I have a 2004 Ford Explorer. Possible sensor or fused replacement?

Yesterday out of nowhere, my gas gauge went all the way down past E, my radio completely stopped working (I can't even see the time), and my windows won't go up or down. My check engine light is now also on.
What could be the problem and how much money would it cost me to fix it?

There's a main fuse that covers all of the dashboard controls in the power distribution box under the hood. I think on your truck it is on the driver's side wheel well back by the brake master cylinder.