Answer: D
Step-by-step explanation:
Standard Deviation σ2 =
Σ(xi - μ)2/N
=(1 - 5.3)2 + ... + (9 - 5.3)2/10
=68.1/10
= 6.81
σ = √6.81
= 2.60959767014
B) σ2 =
Σ(xi - μ)2/N
=(3 - 61.7)2 + ... + (99 - 61.7)2/10
=58414.1/10
= 5841.41
σ = √5841.41
= 76.429117488036
C) (1 - 11.4)2 + ... + (1 - 11.4)2/10
=8758.4/10
= 875.84
σ = √875.84
= 29.59459410095
D) (79 - 79)2 + ... + (79 - 79)2/10
=0/10
= 0
σ = √0
= 0
I hope this helps, mark as Brainliest please.
Answer:

Step-by-step explanation:
we know that
The area of the polygon is equal to the area of a square plus the area of four congruent triangles
so
![A=b^2+4[\frac{1}{2}(b)(h)]](https://tex.z-dn.net/?f=A%3Db%5E2%2B4%5B%5Cfrac%7B1%7D%7B2%7D%28b%29%28h%29%5D)
where

substitute
![A=8^2+4[\frac{1}{2}(8)(4)]](https://tex.z-dn.net/?f=A%3D8%5E2%2B4%5B%5Cfrac%7B1%7D%7B2%7D%288%29%284%29%5D)

<span>An equiangular triangle is a triangle where all three interior angles are equal in measure.</span>
The answer would be commutative.
Hope this helps !
Photon