Answer:
They can either decrease the confidence level or increase the sample size, that is, survey more students.
Step-by-step explanation:
The width of a confidence interval is given by:

In which z is the critical value correponding to the confidence level(higher confidence level, higher z is),
is the standard deviation of the population and n is the size of the sample.
The students realize that this interval contains a large margin of error. What can they do to make a narrower interval?
Looking at the formula for M, they can either decrease the confidence level or increase the sample size, that is, survey more students.
Answer:
74.31353
=74 m
Step-by-step explanation:
given that three locations are marked next to a river. Points B and C are on the same side of the river, and point A is on the other side of the river. To find the distance AB across a river, a distance BC of 241 meters is laid off on one side of the river. It is found that the angle at point B is 108.6° and the angle at point C is 14.9°.
we have information about triangle ABC as side BC =241, Angle B = 108.6 and angle C = 14.9 degrees.
Hence this is an obtuse scalene triangle.
Angle ∠A = 56.5° (III angle)
Using sine formula we get

So distance AB is 74 metres.
-16t^2+400=0
16t^2=400
take square root on both sides.

4t=20
t=20/4
t=5
(n+20)*2 = 99.2
distribute
2n + 40 = 99.2
subtract 40 from each side
2n = 59.2
divide each side by 2
n = 29.6