It means "do you understand" in an aggressive and standoffish manner. As in "If you show your face here ever again, you will cease to exist... you dig it!"
RFP is not an idiom. It's an abbreviation.
It's not really an idiom. It means "what are you thinking about."
It is not an idiom, it means your nose is itching.
idiom means expression like a page in a book
It's not an idiom. It means the tip of your nostril.
"Sieve" is not an idiom. See the related link.
This is not an idiom. It is a measurement. $100,000 is how you write it in numbers.
Simply its mean a bully.
The idiom your blood is boiling usually means that you are mad/furious.
Nothing. You have left out part of the idiom. Perhaps you mean "your hands are tied," which means that you have no power to do anything in a given situation.
"Penniless" is not an idiom. It means that you don't have a penny to spend. It's used as an exaggeration to mean that you don't have any money.
I think it means that that person agrees with that others persons idiom and that it fit that question that the teacher or whoever asked that question.