3. A random variable X is normally distributed. It has a mean of 43 and a standard deviation of 4 . A sample of size 21 is taken. a) (1 pt) Can we say that this sampling distribution is normal? Why or why not? b) Find the mean and the standard deviation of this sampling distribution of the sample mean. c) (1 pt) Find the probability that the mean of the 21 randomly selected items is less than 42.