An American society of investor's survey found 30% of individual investors have used a discount broker. In a random sample of 10 individual ( 6 Marks)

( n =10 = 0.30 )

A. What is the probability non of them have used a discount broker

B. What is the probability that exactly one of them used a discount broker?

c. What is the probability that at most 2 of them used a discount broker ?

d. What is the probability that more than 2 used a discount broker?

e. What is the probability that at least 8 of them used a discount broker?

f. Determine the mean and standard deviation of the distribution