Answer:
a.1.90 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
.
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.
In this question:

So

So the correct answer is:
a.1.90 years
Answer:
7
/8
0.875
Step-by-step explanation:
X = 2y + 7 ...............(1)
2x + 2y = 200 ........(2)
Substituting the expression for x in equation (1) into equation (2) gives
2(2y + 7) + 2y = 200 .....(3)
Equation (3) simplifies to
6y = 186
Therefore y = 31 feet.
Substituting the value for y into (1) gives
x = 69 feet.
Answer:
C
Step-by-step explanation:
Retangular prisms volume= lengthxwidthxheight
therefor you have to include all three number making you answer C