Q1) According to Information Almanac. 80% of adult smokers started smoking before turning 18 years of age. Assume 10 smokers, 18 years of age or older are arbitrarily chosen and number of smokers who started smoking before 18 is recorded.

i) Determine the probability that exactly 8 of them started smoking before 18 years of age.

ii) Determine the probability that at least 8 of them started smoking before 18 years of age.

iii) Determine the area under the standard normal curve that lies between z=-2.55 and 2.55

iv) Determine the Z score such that the area under standard normal curve to the left is 0.85

v) Determine the probability P (Z<-0.61).