It is reasonable to model the number of winter storms in a season as with a poisson random variable. suppose that in a good year the average number of storms is 4, and that in a bad year the average is 5. if the probability that next year will be a good year is 0.6 and the probability that it will be bad is 0.4, find the expected value and variance in the number of storms that will occur.

Absolute value graph shifted point 5 up

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.

Any pictures or something i need more info