When Xochitl runs the 400 meter dash, her finishing times are normally distributed with a mean of 84 seconds and a standard deviation of 2.5 seconds. Using the empirical rule, determine the interval of times that represents the middle 68% of her finishing times in the 400 meter race

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50 ! pls ! 12.  building codes regulate the steepness of stairs. homes must have steps that are at least 13 inches wide for each 8 inches that they rise.

a. discuss how to find the slope of the stairs.
b. describe how changing the width or height affects the steepness of the stairs.

The pyramid shown has a square base that is 24 centimeters on each side. the slant height is 16 centimeters. what is the lateral surface area?