Answer:
b.
Explanation:
-vesign shows the lens is <em><u>C</u></em><em><u>O</u></em><em><u>N</u></em><em><u>C</u></em><em><u>A</u></em><em><u>V</u></em><em><u>E</u></em>
<em><u>f</u></em><em><u>=</u></em>1/power
<span>2.56 sec (t=1/0.39)
f=3.9/10</span>
Average speed = Distance traveled / time taken
In this case Time taken = Difference in hours between 3 PM and 9 AM
= 6 hours
Total distance traveled = 350 km + 250 km
= 600 kilometers
So average speed = 600/6 = 100 km/hr
Average speed of bus = 27.78 m/s
So the bus's average speed = 27.78 m/s or 100 km/hr.
The energy of the wave decreases gradually