Question

alguem pode me ajudar por favor ?

Answer 1

a) Mark lives farther from you than James does.

b) Paul is the thinner guy i've ever met. He looks sick.

Answer 2

a. Mark lives further/farther from you than James does.

b. Paul is the thinnest guy I've ever met.

Regarding B, you must use the superlative form there because you're comparing one person to a specific group of people. If you were comparing one person to another person, then using the comparative form would be correct.