plzzz explain me your questions
A and C, The Color and Texture of the material.
Refer to the diagram shown below.
The following discussion assumes a simplistic analysis that ignores air resistance and variations in the terrain that the missile travels over.
Let the launch velocity be V₀ at an angle of θ relative to the horizontal.
The horizontal component of velocity is V₀ cosθ.
If the time of flight is

, then

where r = the range of the missile.
Also, the time, t, when the missile is at ground level is given by

where g = acceleration due to gravity.
t = 0 corresponds to when the missile is launched. Therefore

Therefore

Typically, θ=45° to achieve maximum range, so that

This analysis is more applicable to a scud missile rather than a powered, guided missile.
Answer:

Usually, θ=45°
No
Explanation:Brooo it does not contribute to the eco system
The original frequency of horn of Car A is 1071 Hz.
Explanation:
Doppler effect describes the change in the frequency of sound waves with respect to the observer. As the sound waves emitted from a source need to travel the air medium to reach observer, it will undergo loss in energy. So there will be change in its frequency compared to original frequency. Depending upon the direction of travel of source and observer the shifting of frequency will vary.

Here vo is the observer velocity and vs is the velocity of the source. So Vo = 15 m/s as car B is the observer and Vs = 35 m/s as car A is the source. And f is the frequency of sound wave at source that is car A.
Similarly, the doppler shift in frequency is the frequency of sound heard by car B which is f' = 1140 Hz. And v is the speed of sound that is v = 343 m/s
1140 = 
f = 1140/1.0649= 1071 Hz.
Thus, the original frequency of horn of Car A is 1071 Hz.