Wher is the image add it for us
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.
Answer:
Creating large preserves in biodiversity hotspots
Explanation:
- In order to preserve the biodiversity hotspots, humans must create biodiversity hotspots which are regions that will nurture, preserve and protect the species from the danger of going extinct in the wild or being hunted by other predators or men.
- There will help protect them from dangers and improve the biodiversity of the planet. It will add to the ecological productivity of the environment.
I believe the answer is option C 1.8 kg•m/s to the east