as/like

Hi everyone,
I've some difficulties if to use as or like in certain sentences, I've read the grammar rules but I'm not sure if I understand them thoroughly. Could you please take a look at those examples and tell me if they're correct? Thanks!

He did it like his father.
He did it as his father would have done it.

She looks exactly like her sister.
She looks exactly as her sister does.

Brian works as a postman.
He works like a madman.

I hate movies of the sort like Steven Segal movies.
He's acting as a fool would act.