Answer:
We are given:
Confidence level = 99%. Therefore, the critical value at 0.01 significance level using the standard normal table is given below:

Margin of error is given in the question as:

Since the previous proportion is not given, therefore, we need to assume 
Therefore, the sample size is:




Therefore, 664 sample observations are required.
Answer:
The distance of flag post from Y is 38.13 m
Step-by-step explanation:
Consider point Y at the intersection of both lines as shown below. Now the point X lies 34 meter from point Y in east direction.
Now flag pole at point X lies at a bearing of N18°W. That is at point X from north, flag post makes an angle of 18° towards west.
Similarly flag pole at point Y lies at a bearing of N40°E. That is at point Y from north, flag post makes an angle of 40° towards east.
Consider ∆ AXY as right angle triangle. Therefore measure of angle FXY is,



Consider ∆ BYX as right angle triangle. Therefore measure of angle FYX is,



Refer attachment 1.
From diagram consider the triangle FYX. To find the third angle that is ∠YFX can be calculated by using angle sum property of triangle.
∠YFX+∠FYX+∠FXY=180°
∠YFX+50°+72°=180°
∠YFX=58°
Refer attachment 2.
Now the distance FY can be calculated using sin rule as follows,

Substituting the values,

Simplifying first two terms,
Cross multiplying,


m
We can solve this problem by using the distance formula. The distance formula is:
We can now put in values and solve.


