Answer:
The margin of of error for a 95% confidence interval for the population mean is of 1.39 years.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.96.
The margin of error is:

In which
is the standard deviation of the population and n is the size of the sample.
Population standard deviation of 3 years
This means that 
Sample of 18 voters
This means that 
Margin of error:



The margin of of error for a 95% confidence interval for the population mean is of 1.39 years.
I would say B since it is x Down 7 units which is subtraction so probably B.
One way of solving this problem can be Heron's formula. It is a formula that allows us to compute the area of a triangle, knowing the length of its three sides.
For the sake of clarity, let's assume that the point in the top-left lies in the origin, and let's call it point A. Then, the "middle" point is point B, and the bottom-right point is point C.
If we fix the coordinate axis with the origin in A, we have the following coordinates for the three points:

We can compute the length of any side using the formula for the distance between two points:

Plugging the approriate values, we get the following lenghts:

Now that we have the lengths, we can use Heron's formula: given the side lenghts
and the semiperimeter
, the area is given by

If you plug our values, you will get an area of 6.5. So, unless I'm mistaken, none of the answers seem to mach, whereas 7 seems the best approximation.
Answer:
0.8
Step-by-step explanation:
its 0.8 cause you divid 4/5
Answer: go to edit my profile then touch profile pic
Step-by-step explanation: