Solve the following problem:
Q1. A coin is tossed 4 times. Let X denote the number of heads which appear in 4 tosses.
a) Construct a probability distribution for X
b) Find P(X>2)
c) Find the expected value of X
d) Find the variance and standard deviation of X
Q2. The probability that a randomly selected elementary or secondary school teacher from a city is female is 0.68, holds a second job is 0.38, and is female and holds a second job is 0.29. Find the probability that an elementary or secondary school teacher selected at random from this city is female or holds a second job.
Q3. Suppose the statistic final exam has 10 multiple choice questions, each with 4 choices. If a student randomly guesses the answers, what is the probability he will pass the final exam. (Assume the student passes with 60 or higher)