I NEED TO KNOW A LAW - RIPPED MONEY ($20 BILL)

I need to know the law that has to do with ripped money and if it is'is not still legal tender. A link would be great, thanks.

If the bill is ripped in half and taped up it's still legal tender. as long as the two serial #'s are the same it's good. If it's totally shredded then you've got a problem. How bad is the rip??