PLEASE HELP ASAP ???

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?

If a + b = 4, what is the value of |4 – a| + |4 – b|?

Evaluate f(x) when x = 3. f(x) = 16x? +2 if 6 < x < 9 112 if 9 x < 13 a: 110 b: 56 c: 74 d: 12