I was wondering if someone could help me with these 2 questions?

Let the closed interval [a , b] be the domain of function f. the domain of f(x - 3) is given by (a) the open interval (a , b) (b) the closed interval [a , b] (c) the closed interval [a - 3 , b - 3] (d) the closed interval [a + 3 , b + 3]

How many lines can be drawn through points j and k? 0 1 2 3

Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?