Answer:
554 executives should be surveyed.
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 Z-table as such z has a p-value of
.
That is z with a pvalue of
, so Z = 1.96.
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.
Standard deviation of 3 hours.
This means that 
The 95% level of confidence is to be used. How many executives should be surveyed?
n executives should be surveyed, and n is found with
. So






Rounding up:
554 executives should be surveyed.
Answer:
a.$167.03
Step-by-step explanation:
283 rounded to the nearest ten is 280
When rounding to the nearest ten look at the number to the right of the place you are rounding. In this case it is the 3. If the number is 5 or higher you go up to the nearest ten. If the number is lower than 5 like it is in this number you round down to the nearest ten.
Answer:
k = 15.94
Step-by-step explanation:
57 degrees because 180-123= 57 degrees