When Sahara runs the 400 m dash, finishing times are normally distributed with a mean of 84 seconds in a standard deviation of 1.5 seconds using the empirical rule, what percentage of races while her finishing time be between 81: 87 seconds?

Select the correct answer from each drop-down menu. a system of equations and its solution are given below. system a complete the sentences to explain what steps were followed to obtain the system of equations below. system b to get system b, the equation in system a was replaced by the sum of that equation and times the equation. the solution to system b the same as the solution to system a.]