Answer:
Commutative
Step-by-step explanation:
Given

Required
What law is applied
The applied law is commutative law of addition.
This law states that:

So:

When the positions of 2 and b are interchanged, we have:

Remove bracket

√24=√4×6=2√6
c)2√6
---------
Answer:
(a) σ² = 144
(b) s² = 12
Step-by-step explanation:
(a) Population variance σ² = ∑(X -
)² / N
The arithmetic mean 


σ² = 
= 
= 
= 
σ² = 144
(b) 

= 12
Question a:
f(6) = (6)² + 2(6) + 8
f(6) = 36 + 12 + 8
f(6) = 56
Question b:
f(x+4) = (x+4)² + 2(x+4) + 8
f(x+4) = x² + 8x + 16 + 2x + 8 + 8
f(x+4) = x² + 10x + 32
Question c:
f(-x) = (-x)² + 2(-x) + 8
f(-x) = x - 2x + 8
The answer is the last one 300