Hey There,
Movement of earth around sun and tilt of earth on it's axis causes seasons on earth. So, the answer is B.
Hope this helps!
Answer:
Option D: More than 90
Explanation:
Thickness probably depends on temperature. The higher the temperature, the more aliens we expect to be thin.
Answer: The answer: The car is moving away from you.
Both A and C are true as Car can be moving in line away from you or has component of velocity in opposite direction.
Explanation:The decrease in the frequency of the sound is the result of Doppler's effect. A/c to Doppler's effect the frequency of received sound of source is changed if it is moving relative to the receiver, i.e. the distance between them is changing due to motion.
The general formula of Doppler's Effect is attached as the picture.
In this formula v_D is the velocity of Detector i.e the receiver relative to wind. While v_s is the velocity of source relative to wind and v is the velocity of sound.
The Doppler's effect is not effected by the velocity of wind as the wind itself could not change the distance between the two objects i.e. you and the car. Wind velocity can change the speed of sound and its wavelength but the change does not effect the frequency.
Hence if we assume the car to be moving with velocity v_c and you are stationary

hence the frequency is reduced.
It i believe it would be 7.3 × 10∧3.
correct me if im wrong
The speed of waves are determined by the frequency of the push(wind). This really determines what the wave is being pushed by. If it were a Tsunami it would be by the frequency of the Tsunami if it were from the wind then the winds frequency would determine it's speed. Also the wavelength determines the speed because of the wight it has, but again something has to cause this wave to move.