Answer:
The correct answer is D. It is not true that cluster sampling uses randomly selected clusters and samples everyone within each cluster.
Step-by-step explanation:
Cluster sampling is a method of collecting samples and statistical data, by means of which a certain group formed by people, things, events, etc., is taken as a sample, which are not considered individually but as part of a whole, which is in turn a proportional representation of the universality of samples available in the field.
Now, since this type of sampling allows to embrace large groups of sample units, data are not always obtained from all the components of the cluster, but from those necessary to be able to quantify the desired statistics.
X^2+4+10=0
x=(-4(+/-)root16-40)/2, so we now know that the zeros are imaginary, because you can't square root a negative number and 16-40 is -24
so the two roots are…
-2+iroot6 and -2-iroot6
Step-by-step explanation:
It is 64*0.32=20.48 minutes or 20.5 minutes.
Answer: it will take 7 seconds
Step-by-step explanation: 9 x 7 = 63
Answer:

Step-by-step explanation:
step 1
Find the area of the plate
The area of a circle is given by the formula

we have
---> the radius is half the diameter
substitute

step 2
Find the area of the square napkin folded (is a half of the area of the square napkin)
we know that
The diagonal of the square is the same that the diameter of the plate
Applying Pythagorean theorem

where
b is the length side of the square
we have

substitute

solve for b^2
-----> is the area of the square
Divide by 2

step 3
Find the area of the space on the plate that is NOT covered by the napkin
we know that
The area of the space on the plate that is NOT covered by the napkin, is equal to subtract the area of the square napkin folded (is a half of the area of the square napkin) from the area of the plate
so

simplify
