You flip 18 coins once. The coins are weighted so that the probability of a head on any one coin is .70. What is the probability of getting exactly 16 heads?

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%