The Speed of Sound in Air Is Approximately $340 \mathrm {~m} / \mathrm { s } .$

The speed of sound in air is approximately $340 \mathrm {~m} / \mathrm { s } .$ .The speed of sound in steel is
approximately $5900 \mathrm {~m} / \mathrm { s } \text {. }$ If your friend strikes one end of a steel pipe with a hammer while you
listen at the other end, you will hear two distinct sounds: one traveling through the air and the
other traveling through the steel pipe.If the pipe is 700 meters long, how much time elapses
between the two sounds?