The answer is of this question is B.
Answer:
The speed in of the plane is 115.47 m/sec
Step-by-step explanation:
Given:
Height at which the plane is flying = 6000 m
Angle of elevation at the radar base = 30 Degrees
Angle of elevation at the radar base after one minute = 60 Degrees
To Find:
The Speed of the plane in meter per second = ?
Solution:
Let us use the tangent of the angle to find the distance (d) to a point directly below plane:
<u>when the angle is 30 degrees</u>



d1 = 10392.3 meters
<u>when the angle is 60 degrees</u>



d2 = 3464.1 meters
<u>distance travelled by aircraft in 1 min is </u>
=>d1 - d2
=>0392.3 - 3464.1
= 6928.2 m/min
<u>Now converting to m/sec</u>
=>
=>115.47 m/sec
It must be a parallelogram.
Percent means per 100/ out of 100.
3/20= x/100
20*5=100
3*5=15
15=x
Final answer: 15%
Here are the answers for 10 and 12