Respuesta :
Answer:
Option D. 25636 ft
Step-by-step explanation:
From the given right triangle,
Observer is at the point O and he observes the plane flying at point P.
Angel of elevation of the plane is 55° and altitude of the plane was 21000 ft.
To get the distance OP we will apply Sine rule in the given right triangle,
Sin 55 = [tex]\frac{h}{x}[/tex]
Sin 55 = [tex]\frac{21000}{x}[/tex]
x = [tex]\frac{21000}{\text{sin}55}[/tex]
x = 25636.27
x ≈ 25636 ft
Therefore, distance between the plane and observer is 25636 ft.
Option D. is the answer