Answer:
a) 
b) The should sample at least 293 small claims.
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
, which means that the answer of question a is z = 1.645.
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.
(b) If the group wants their estimate to have a maximum error of $12, how many small claims should they sample?
They should sample at least n small claims, in which n is found when
. So







The should sample at least 293 small claims.
Answer:
110
Step-by-step explanation:
Answer: The length is 510 and the width is 110.
Step-by-step explanation:
To find the area of a rectangle, you will have to add the 2 times the length plus 2 times the width because a rectangle have 4 sides. Two widths and two lengths.
You can now use the formula P= 2l + 2w
were P is the perimeter , l is the length, and w is the width.
the length is 400 more than the width, so we can represent that by the equation, l = w + 400
And now we know that the width is w.
So now we will input the perimeter, length, and into the formula to solve for w.
1240 = 2(w + 400) + 2w
1240 = 2w + 800 + 2w
1240 = 4w + 800
-800 -800
440 = 4w
w = 110
L= 110 + 400
L = 510
Check :
1240 = 2(510) + 2(110)
1240 = 1020 + 220
1240 = 1240
Answer: Choice D 
Reason:
Exponential functions have the variable in the exponent.
Choice A is a polynomial, which means we can rule it out. Choice B is a log function, so we can rule it out also.
Choice C is a rational function because it is a ratio of two polynomials. This rules out choice C.
Choice D is the only function with the variable in the exponent. That is assuming you meant to say
instead of 
1/4=.25
0.5=0.5
10/25=.4
Answer= 1/4, 10/25, 0.5