Answer:
fo = 378.52Hz
Explanation:
Using Doppler effect formula:

where
f' = 392 Hz
C = 340m/s
Vb = 20m/s
Va = 31m/s
Replacing these values and solving for fo:
fo = 378.52Hz
Answer:
D
Explanation:
The color you see is the color the object reflectes. The rest of the color are absorbed by that object.
1900 millimeters thats wht i got
If you put a penny in each light spot the penny that the light is shining on will recive the most energy.