The size of frogs in a pond is normally distributed. The mean size is 23.0 g with a standard deviation of 2.5 g.

a) What percentage of frogs are more than 26 g? and less than 19 g?

b) What is the probability that a random frog will weigh between 24 g and 28 g?

b) A herpetologist catches 8 frogs. What is the probability that the mean size of those frogs is at least 25.5 g (assume frogs are caught at random)?