I have three questions that I am not sure of: Help on any of them is greatly appreicated

1) Assume the probability that you will make a sale on a given phone call is .19

a) Find the probability that you will not make a sale on the first three calls ie. your sale will be made after the first three calls

b) Find the probability that your fourth sale is made on the eighth call

2) Among 90 cities that professional group is considering for its next three annual conventions, 36 are in the western part of the united states use the binomial approx to the hypergeometric distribution to find the probability that at most one of the three conventions will be held in the western part of the US

3)According to an airline report roughly 1 piece of luggage out of every 200 that are checked is lost. Suppose that a freq flyer will check 120 bags over a year approx the probabilty that she will lose 2 or more pieces of luggage