Question 2: Introduction to Normal Distribution. A. Which one of the following is true for normal distribution? a. A normal distribution is bell-shaped and symmetric. b. A normal distribution is dened completely by the mean u and variance oz. c. Increasing the mean shifts the curve to the right whereas increasing the standard attens the curve and increases its spread. d. All of the above are true. ANSWER: B. Suppose X is a NORMALLY distributed random variable with mean u and standard deviation 0. The formula that is used to transform X into a standard normal distribution is 111 = p and 112 = I-l2 + 02. C. The Mean of a standard normal variable is =E(Z}= 12.7 D. The variance of a standard normal variable is=V(Z)= 1.10 E. Find the P(Z