A standard deviation of 0 means that nothing deviates, in other words all observations are 40. So 40 is the smallest, the largest, all of that!
Let's call them B, M, C, L
We'll have (without reapeating):
B,M
B,C
B,L
M,C
M,L
C,L
Ok so what you do is you do 52*24.25=1261. Then you divide 1361.88 by 1261 and you would get 1.08, nut I may be wrong so recheck yourself to make sure
<span>by adding an identical classroom that has adjustable windows
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