It can be both flat or it can be when you have new eyeglasses on and you look down it makes you think the ground looks like that but its not
Answer:
Total time taken=110 seconds
Total distance traveled=480m
Explanation:
First of all, we find the total time taken:
For that, we use the formula : Distance/Speed= Time
Time for part 1 : 200/5=40 seconds
Time for part 2 : 280/4=70seconds
Total time taken=110 seconds
Total distance traveled=480m
Average Speed= 480/110=4.36 m/s
Total displacement=200-280=-80m (Since this is displacement, we need to find the distance between the initial and final point. Also, I've taken east direction as positive and west as negative)
Average Velocity=-80/110=-0.72 m/s
OR 0.72m/s towards west.
I think so it ans wold be d.because if the source approaches the observer more and more wavefront will pass and it get squeezed.so wavelength decreases and frequency increases.