Please help!! This question determines if my friend passes or fails math this year and he has no clue how to solve it
(Last answer choice is 17 btw)

Answer this question, only if you know the answer. 30 points and brainliest!

F(n + 1) = f(n) – 8. if f(1) = 100, what is f(6)?

Sherrie is baking a pie for her family. she leaves the room and comes back to 35% of the pie having been eaten before she can put the topping on. how much 1 square inch strips of dough will she need for the top, now that a portion is missing? round your answer to the nearest while nimber.