Answer:
458
Step-by-step explanation:
Margin of error = critical value × standard error
At 99% confidence, the critical value is z = 2.576.
The standard error is σ/√n = 5.4/√n.
Given the desired margin of error is 0.65:
0.65 = 2.576 × 5.4/√n
n = 458
Answer:
Given speed of trolley = 125 meters per minute

Now we know that
Distance= Speed x time
Thus for the first case since the time of travel is less than 450 seconds thus the distance traveled is less than
Distance < 2.083 x 450 =937.5 meters
hence depending on the given information we cannot come to any conclusion weather the distance travelled is less than 800 m or greater than 800 m.
For the second case
since the time of travel is greater than 400 seconds
Thus the distance traveled is

which is greater than 800 meters.
2%
is the correct answer i presume