What is the value of a1 in the sequence?

−4,−2,−1/2,−1/4,...

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

Reading tests are compared for two students. sara got 98, 100, 65, 78, 98, 46, 100, 100, 45, and 50 on her reading test. lee got 97, 67, 89, 99, 100, 45, 79, 89, 58, and 67 on his reading test.

Which expression represents the total perimeter of her sandwich, and if x = 1.2, what is the approximate length of the crust?