Steps to solve:
3^2 • 3^-8 • 3^0
~Apple exponent rule [ a^b * a^c = a^b+c ]
3^2-8+0
~Simplify
3^-6
~Use exponent rule [ a^-b = 1/a^b ]
1/3^6
~Simplify
1/729
Best of Luck!
Answer: σ: 2.76
Step-by-step explanation:
Count, N: 5
Sum, Σx: 125
Mean, μ: 25
Variance, σ2: 7.6
Steps
look at attached pic for formula
σ^2 = 

⇒ 
⇒ 7.6
σ = 
⇒ 2.756809750418
⇒ or 2.76
Use 80% *25 than you can get 20.
14/4 > 1 is what it looks like.