Clarifications on the following arguments are required.

Are they 

1) valid/sound 

2) Invalid/unsound 

3) Valid/unsound 

P1: All people need food and sleep to live. 

P2: Students are people. 

C: Students need food and sleep to live. 

P1: If I were a rabbit, I would be a mammal. 

P2: I am a mammal. 

C: I am a rabbit. 

P1: Tigers and housecats are both cats. 

P2: Tigers are fearsome predators. 

C: Housecats are fearsome predators.