A promises her son B $ 1,000 per month if he begins his engineering studies at university. A's brother, C offers B a place in his house if B promises...

A promises her son B $ 1,000 per month if he begins his engineering studies at university. A’s brother, C offers B a place in his house if B promises to finish his studies. B offers his girlfriend D $ 50 per month if she will drive him to the university each morning. Are any of these agreements enforceable?