Answer:
a) Margin of error = 166.311
b) sample size ≥ 62
Step-by-step explanation:
Given:
Average cost = $1599
Sample size = 50 persons
Standard deviation = $600
Confidence level is 95%
a) Margin of error = 
Now for confidence level of 95% z-value = 1.96
Thus,
Margin of error = 
or
Margin of error = 166.311
b) For Margin of error ≤ 150
≤ 150
or
≤ 150
or
≤ √n
or
√n ≥ 7.84
or
n ≥ 61.4656
Therefore,
sample size ≥ 62
Answer:
Option c.
No damping
Step-by-step explanation:
We can easily solve this question by using a graphing calculator or any plotting tool.
The function is
f(x) = (√11)*cos(3.7x)
Which can be seen in the picture below
We can notice that f(x) is a cosine with maximum amplitude of (√11). Neither this factor nor the multiplication of x by 3.7 serve as a damping factor since they are constants.
f(x) does not present any dampening