In a large city 1 person in 5 is left handed.

i) find probability that in a random sample of 10 people exactly 3 will be left handed

ii) find the most likely number of left handed people in a random sample of 12 people

iii) find the mean and standard deviation of the number of left handed people in a random sample of 25 people

iv) How large must a random sample be if the probability that it contains at least one left handed person is to be greater than 0.95?