What is really needed is the distance from each grade to the mean not the difference. You could take the absolute value of each difference and then calculate the mean. This is called the mean deviation, i.e. mean deviation = , where n is the number of students in the class. For class 1 this is 64/5 = 12.8.
1. Determine if there is a roof leak. Look for mold or mildew in attics or on walls. Look for discoloration on ceiling tiles or drywall. Look for wet, moist and rotting wood in crawl spaces, around chimneys or other additions, such as skylights and vents.. Check the attic for dyed areas. Follow the dye path from where it begins to where it comes out to find the leak. There may be multiple points of entry, so if you find one point, continue to search thoroughly until you are satisfied that there are no more leaks.
Agilent 7697A Headspace Sampler Leak Testing the Headspace Sampler Parts Supplied 1 Leak Check General Procedure 2 Flow Paths 4 Checking for External Leaks 6 To Run the Restriction and Pressure Decay Test 8 To Run the Cross Port Leak Test 18 To Check for Leaks in the Transfer Line 22 This document discusses leak testing in the headspace sampler (HS). Chromatographic symptoms such as loss of sensitivity can result from leaks and restrictions. Use the following set of tests for verifying leaks and