Hair is how most people express themselves and it wrong for people to tell them to change it just because they don’t like it.
For 2.a the table is linear and the difference is 0.5
For 2.b the table is non- linear because if you divide y from x for each pair then it should all be the same number but it`s not.
A transitive verb has a direct object and usually, the subject is doing the action towards that object. The subject performs the action and the object receives the actions. So I believe D is the answer.