Which one of the four diagrams represents X’?

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%

What is always true when two whole numbers are subtracted?

If a is a nonzero real number then the reciprocal of a is