Proofs for domains and ranges of relations

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How do I prove/ find counterexamples for the following?

Dom(R∩S)=Dom(R)∩Dom(S)

Rng(R∩S)=Rng(R)∩Rng(S)

Dom(R-S)=Dom(R)-Dom(S)

Rng(R-S)=Rng(R)-Rng(S)

I know how to prove Dom(R∪S)=Dom(R)∪Dom(S)and Dom(R∩S)=Dom(R)∩Dom(S), but am unsure with how to proceed with these. Could someone provide hints/ preliminary steps for each?

I also believe that all are true and can be proven.. is this not the case?