Answer:
distance: 2200 ft
distance: 550n ft
Explanation:
First, we need to convert 750 miles per hour into feet per second.
Since 1 mile = 5280 feet and 1 hour = 3600 seconds, we get:
[tex]750\text{miles}/\text{hour}\times\frac{5280ft}{1mile}\times\frac{1h}{3600s}=1100ft/s[/tex]Then, the distance can be calculated as the velocity times time.
It takes about 4 seconds to hear the echo, so it reaches the canyon wall after half of this time. It means that the distance is equal to
[tex]\begin{gathered} \text{distance = velocity }\times time \\ \text{distance}=1100ft/s\times\frac{4s}{2} \\ \text{distance = 2200 ft} \end{gathered}[/tex]If it takes n seconds to hear the echo, the time will be n/2 seconds, so the distance will be
[tex]\begin{gathered} \text{distance}=1100\times\frac{n}{2} \\ \text{distance}=550n \end{gathered}[/tex]Therefore, the answers are:
distance: 2200 ft
distance: 550n ft