Why not look up "standard deviation" yourself, to be sure? But yes, the std. dev. is the sqrt of the variance.
Answer:
B. 0.83
Step-by-step explanation:
I calculated it logically
For the difference to be positive, when both the minuend and the subtrahend are positive, the former must be greater than the latter.
Therefore
minuend = 2 ⇒ subtrahend = 1 ← 1 number
minuend = 3 ⇒ subtrahend = 1,2 ← 2 numbers
minuend = 4 ⇒ subtrahend = 1,2,3 ← 3 numbers
minuend = 5 ⇒ subtrahend = 1,2,3,4 ← 4 numbers
minuend = 6 ⇒ subtrahend = 1,2,3,4,5 ← 5 numbers
1+2+3+4+5=<u>15</u>
