A certain birth defect occurs with probability, p= XXXXXXXXXXAssume that n= 4000 babies are born at a particular large, urban hospital in a given year. Use the POISSON cell function to answer the...

A certain birth defect occurs with probability, p= .0001. Assume that n= 4000 babies are born at a particular large, urban hospital in a given year. Use the POISSON cell function to answer the following questions. Hint: you will have to calculate the expected number of babies born with the defect.

What is the probability that there will be no more than 2 babies born with the defect?

I don't know what poisson fxn to use. I was think poisson.dist (X, mean, cummulative TRUE), but I don't know what X or the mean is.