A random variable is normally distributed with a mean () = 50 and a standard deviation () = 5. a) Sketch a normal curve for the probability density function. Label the horizontal axis with values of 35, 40, 45, 50, 55, 60, and 65. b) What is the probability the random variable will assume a value between 45 and 55? c) What is the probability the random variable will assume a value between 40 and 60?