Decide whether the given expression is a polynomial and tell why or why not 1/x^4 + 5x^2 – 4x + 1

Jackie purchased 3 bottles of water and 2 cups of coffee for a family for $7.35. brian bought 4 bottles of water and 1 cup of coffee for his family for $7.15. how much does each bottle of water cost? how much does each cup of coffee cost? i need this done

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

Over the last 8 nights, elyse earned the following in tips: {105, 120, 84, 95, 100, 132, 140}. if she earns $140 a night for the next four nights, which measure of center would increase more, the mean or median?