A wildlife biologist determines frogs for a genetic trait that may possibly be linked to industrial toxins in the environment. This trait is usually found in 1 of every 9 frogs, so the prevalence is 0.11. A sample of 11 frogs are collected and examined.
(a) The expected number of frogs in the sample with this trait is?
(b) What is the probability that no more than 4 frogs in the sample have this trait?
(c) What is the probability that 3 or 4 frogs in the sample have this trait?
(d) What is the probability that at least 3 frogs in the sample have this trait?