Answer:
each group of the periodic table.
example group 7 - fluorine, chlorine, bromine, iodine, astatine, tennessine
I think it is because it is directly about the north or south pole (I forget) so while all the other stars seem to rotate around because the Earth is rotating but the North Star is directly in the center. Don't take my word though.
To find the mean of a number of numbers, First you add them up.
9.99 + 10.01 + 9.97 + 10.8 = 40.77
Then, you divide the result by how much numbers you have (in this case 4)
40.77 / 4 = 10.1925
So, the mean value is 10.1925.
The deviation is the difference between the number and the mean.
(number - mean = Average deviation)
So you get:
9.99 - mean = 9.99 - 10.1925 = -0.2025
10.01 - 10.1925 = -0.1825
9.97 - 10.1925 = -0.2225
10.8 - 10.1925 = 0.6075
Now to find the Average deviation, you do the same steps as finding the mean. Add them up, and divide by 4 (because there is 4 numbers)
P.S. Negative numbers become positive.
0.2025 + 0.1825 + 0.2225 +0.6075 = 1.215
1.215 / 4 = 0.30375
So, the Average Deviation is 0.30375
Hope this Helps :)
The answer to this question is is d
