THIS IS NOT MY ANSWER i got this from someone else but i think this will help u cause it’s from the same question:
We have our initial unit of speed: 343 m/s.
We want to find how many kilometers sound will travel when the air is at 68 degrees in five seconds.
Step 1: Multiply 343 by five. (1 sec. to 5 secs.)
343 * 5 = 1715
Step 2: Divide 1715 by 1000. (1 m. to 0.001 km)
1715/1000 = 1.715 km/5 secs.
At a temperature of 68°, sound will travel 1.715 km in 5 seconds.
