Answer:
The sample required is 
Step-by-step explanation:
From the question we are told that
The standard deviation is 
The margin of error is 
Given that the confidence level is 99% then the level of significance is mathematically evaluated as



Next we will obtain the critical value
from the normal distribution table(reference math dot armstrong dot edu) , the value is

The sample size is mathematically represented as
![n = [ \frac{Z_{\frac{\alpha }{2} } * \sigma }{E} ]^2](https://tex.z-dn.net/?f=n%20%3D%20%5B%20%5Cfrac%7BZ_%7B%5Cfrac%7B%5Calpha%20%7D%7B2%7D%20%7D%20%2A%20%20%5Csigma%20%7D%7BE%7D%20%5D%5E2)
substituting values
![n = [ \frac{ 2.58 * 9 }{2} ]^2](https://tex.z-dn.net/?f=n%20%3D%20%5B%20%5Cfrac%7B%202.58%20%2A%20%209%20%7D%7B2%7D%20%5D%5E2)

Answer:
A
Step-by-step explanation:
Since 4i is a root, that automatically means -4i is also a root (complex roots always travel in pairs)
So the factored form would look like
<span>(x+4i)(x−4i).</span>
When multiplied out this gives the polynomial
<span><span>x2</span>+<span>16.</span></span>
Answer:
Step-by-step explanation:
The x and y intercepts occur when either x or y = 0
For the y intercept, x = 0
3(0) - 5y + 15 = 0
- 5y + 15 = 0 Subtract 15 from both sides.
-5y = - 15 Divide by - 5
-5y / -5 = - 15/-5
y = 3
For x intercept, y = 0
3x - 5(0) + 15 = 0
3x + 15 = 0 Subtract 15 from both sides
3x = - 15 Divide by 3
3x/3 = - 15/3
x = - 5
xintercept = (-5,0)
yintercept = (0,3)
Y = 12x is a direct variation which is a proportion.
As x increases y also increases.