Hmmm...I don't know what to tell you I can't type out your answer For you.
sorry
Answer:
75 mins or 1 hour 15 min :)
Step-by-step explanation:

and

(f+g)(x) =

combining like terms gives you answer choice B
is there a picture? if there is I cant see it
I think this is a least common multiple question
So they would all arrive on day 504, (which probably is a few years)
8 = 2 × 2 × 2
18 = 2 × 3 × 3
21 = 3 × 7
I might be right I might be wrong, IM not positively sure but yknow