If a coin is flipped 100 times, and the random variable X is defined as "the number of heads that turn up", compute the following:
a) the expected value of X
b) the variance of X
c) the standard deviation of X
d) the probability that there will be between 45 and 55 heads
e) the probability that there will be more than 52 heads
f) the probability that there will be fewer than 46 heads