1) 10% of americans think they have seen a ufo. using a sample of 12 people find each probability using a decimal with 4 decimal places

a. exactly two people believe they have seen a ufo

b. at least 2 people believe they have seen a ufo

c. 2 or 3 people believe they have seen a ufo

2) a multiple choice test with 4 questions and 5 answer possibilities per question, with only one correct answer. to pass the test you must get at least 3 questions correct. if a student randomly quesses what is the probability of her passing?

a. find n

b. find p

c. find q

d. find p (passing)

3) it is known that 90% of people are right-handed. using a sample of 120 random people, let x= # of left-handed people of the selected group (answer with one decimal place)

a)what is the mean of x

b)what is the variance of x

c) find the standard deviation of x