Question 1170949
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            It is strange to me to see this gross mistake in the post of the other tutor.


            So, I came to bring the correct solution/answer.



<pre>
d = k*t


k = {{{d/t}}} = {{{4/20}}} = {{{1/5}}} = 0.2.


In this problem, k is the speed of sound in the air, equal to 0.2 miles per second (approximately).
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