How to Use the Empirical Rule w/ standard normal distribution

In this video tutorial the instructor explains about the concepts of standard normal distribution and the empirical rule and how to use it to solve an exercise. He starts by explaining about standard normal deviation saying that in a standard normal deviation the value of mean is zero and the value of standard deviation is one. Now he draws the standard normal deviation by drawing a bell curve on an axis. Now he points the mean and standard deviations on it. Now using these concepts he goes on and solves the sample example by showing how to apply those concepts. This video explains about the concept of standard normal deviation by solving an example.