In an algebraic expression, what separates the terms?

Hi, can anyone show me how to do this problem? 100 points for this. in advance

Someone answer this asap for the first five terms of a sequence are shown. 5, 11, 23, 47, 95, . . which recursive function defines the nth term in the sequence for n > 1? a. f(n) = f(n - 1) + 6 b) f(n) = f(n - 1) + 48 c) f(n) = 3 • f(n - 1) + 1 d) f(n) = 3 • f(n - 1) - 4

Ablue whale traveled 3112 miles in 214hours. what was the whale's rate in yards per hour? (1 mile = 1,760 yards)