Please help! I don't know what answer b is, but i know a, thank you.

They are corresponding angles
Step-by-step explanation:
We know that x=75⁰ because
[tex]180 - 105 = 75[/tex]
75⁰ is angle EFB
Since we know this, and because we know that AD//EH,
We can conclude that x=75⁰(AD is parallel to EH and angle CBA or x and angle EFB are corresponding angles)