Answer:
It would take 1 s to hear the echo.
Explanation:
Here, the sound covered a total of 340 meters, since it bounces off the canyon wall and travels back to Miles in the form of echo.
The time elapsed can be determined by,
v = [tex]\frac{2D}{t}[/tex]
⇒ t = [tex]\frac{2D}{v}[/tex]
where: v is the speed of sound in air (343 m/s), D is the distance of the nearest canyon (170 m).
So that,
2D = 2 x 170 = 340 m
Thus,
t = [tex]\frac{340}{343}[/tex]
= 0.9913 s
t = 1 s
It takes 1s for Miles to hear his echo.