Answers

2015-12-24T11:33:13+05:30
Ultrasonic waves are inaudible to humans...........................and are used to train animals like dolphins..................................but they r also used to control them as humans are unable to hear it!
1 5 1
2015-12-25T11:29:41+05:30
Ultrasonic waves are inaudible to humans and are used to train animals like dolphins but they r also used to control them as humans are unable to hear it!
0