Answer:
We need to sample at least 1069 parents.
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 
.
So it is z with a pvalue of 
, so 
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
How many parents do you have to sample?
We need to sample at least n parents.
n is found when 
. So
Rounding up
We need to sample at least 1069 parents.
The answer should be 26 hours
Answer:
The answer is A, 18.84.
Step-by-step explanation:
The two points are 6 places apart, so that can be 6 units as radius. To find the circumference of a circle you do r x 3.14 (to abbreviate pi). 6 x 3.14 is 18.84 so A is your answer.
