A rare disease affects one in every one million people on average in the US. A national public health organization investigates a large sample of people in the US. Assume all people investigated are independent of each other in terms of this disease. In each of the questions below, select THE SINGLE correct statement. (a) Assume the people are investigated one after another. Let X be the number of people investigated until the organization finds the first person with the disease. The average and standard deviation of X are about
(b) With X as in (a), the chance that the organization has to investigate 2,000,000 people before finding their first person with the disease is
(c) In a group of 10 people chosen at random by the organization, the probability that at least three people have the disease is equal to