Answer:
The minimum sample size required to create the specified confidence interval is 1024.
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.
What is the minimum sample size required to create the specified confidence interval
This is n when
.






The minimum sample size required to create the specified confidence interval is 1024.
Cost
60+20+10+50+25=165
Tax
165*.06=9.90
Cost+Tax
165+9.90=174.90
75% is 3/4
that's all!!
Hope it helps
They multiplied 3 by itself 4 times, so it’s 3^4