Answer:
B) 81π units²
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Geometry</u>
Radius of a Circle Formula: r = d/2
Area of a Circle Formula: A = πr²
Step-by-step explanation:
<u>Step 1: Define</u>
Diameter <em>d</em> = 18 units
<u>Step 2: Manipulate Variables</u>
Radius <em>r</em> = 18 units/2 = 9 units
<u>Step 3: Find Area</u>
- Substitute in <em>r</em> [Area of a Circle Formula]: A = π(9 units)²
- [Area] Evaluate exponents: A = π(81 units²)
- [Area] Multiply: A = 81π units²
Answer:
atleast 385
Step-by-step explanation:
Given that an electrical power company is looking to expand into a new market. Before they commit to supplying the new area with electricity, they would like know the mean daily power usage for homes there.
Population std deviation = 
Sample size =
STd error of sample mean = 
Margin of error for 95% would be Critical value ( std error)
Here since population std dev is known we can use Z critical value= 1.96

Sample size should be atleast 385
Answer:
12
Step-by-step explanation:
We can use the pythagorean theorem giving us:
a^2+b^2=c^2
(6sqr2)^2 + (6sqr2)^2 = c^2
72+72=c^2
144=c^2
12=c
Answer:
The slope is 3/4
Please correct me if I am wrong please and thank you
Step-by-step explanation:
I use the slope formula 
Plug in (2,1) and (-2,-2)
1-(-2)/2-2
= 3/4
Answer:
11
Step-by-step explanation:
Substitute 3 for b
23 - 4(3)
Multiply 4(3) = 12
23 - 12
Subtract
23 - 12 = 11