Amodel train engine is 6 inches long the real train is 42 feet long what is the scale factor

What is the product of the radical expression. (7-2square root) (8+2 square root)

When only separate discreet points are graphed it is called?

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%