Answer and Step-by-step explanation:
This problem requires the use of trigonometric functions, specifically the tangent trig function.

Plug in the values.

Multiply by x to both sides, then divide by tan(40) to both sides.

Now, plug this into a calculator and rounded to the nearest whole number (foot).
x = 9534.0287
x = 9534 ft.
The answer is 9534 ft., the last option.
#teamtrees #WAP (Water And Plant)
Margin of error, e = Z*SD/Sqrt (N), where N = Sample population
Assuming a 95% confidence interval and substituting all the values;
At 95% confidence, Z = 1.96
Therefore,
0.23 = 1.96*1.9/Sqrt (N)
Sqrt (N) = 1.96*1.9/0.23
N = (1.96*1.9/0.23)^2 = 262.16 ≈ 263
Minimum sample size required is 263 students.