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

Solve the equation -9p - 17 =10 a -3 b. 16 c. 18 d -16

He weights of 2-pound bags of best dog food are approximately normally distributed with a given mean  and standard deviation  according to the empirical rule, what percentage of the bags will have weights within 3 standard deviations of the mean? 47.5%68%95%99.7%