The following table lists the speed of sound in various materials. use this table to answer the question. substance speed (m/s) glass 5,200 aluminum 5,100 iron 4,500 copper 3,500 salt water 1,530 fresh water 1,500 mercury 1,400 hydrogen at 0°c 1,284 ethyl alcohol 1,125 helium at 0°c 965 air at 100°c 387 air at 0°c 331 oxygen at 0°c 316 how long would it take for a sound impulse to travel through an aluminum rod 25 kilometers long? 0.0049 sec 0.071 sec 4.9 sec 0.14