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Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?

Simplify (1/2)4th power a. (1/16) b.(1/8) c.(1/4)