Enzymes questions - cofactors, zymogens, proenzymes, etc

I just want to clear up some things about enzymes in the OCR A level Biology spec -

1. Is it correct to say that the distinguishing difference between the roles of inorganic cofactors and organic cofactors is that inorganic cofactors help to form the correct shape of the active site, and organic cofactors move chemical groups between enzymes (how does this work as well?)?

2. are organic cofactors minerals and ions, whereas organic cofactors are organic molecules? If so, then why are some prosthetic groups (which from my understanding are a sub-category of cofators) also ions e.g. zinc ions which are a prosthetic group for carbonic anhydrase?

3. does 'loosely bound' have the same meaning as 'reversible' in terms of the cofactor/inhibitor?

4. what is the difference between zymogens, proenzymes, apoenzymes and holoenzymes?

Much appreciated, thanks