| name the waves used for echo depth sounding | 1.41 | 0.3 | 4053 | 43 | 7 |
| echo of the waves | 1.98 | 1 | 4379 | 17 | 31 |
| getting an echo with sound waves | 1.18 | 0.6 | 4237 | 32 | 45 |
| what is echo sounding | 0.82 | 0.9 | 422 | 21 | 3 |
| what is echo sounding technique | 1.01 | 0.1 | 4946 | 31 | 38 |
| what behavior of sound waves causes echoes | 0.34 | 0.5 | 9701 | 42 | 58 |
| wave echo cave sound | 1.47 | 0.5 | 905 | 20 | 90 |
| echo of the depths | 0.17 | 0.2 | 6859 | 18 | 34 |
| how does echo sounding work | 0.41 | 0.6 | 8501 | 27 | 45 |
| what is the best sounding echo device | 0.58 | 0.5 | 689 | 37 | 27 |
| what is an echo sound | 1 | 0.8 | 7729 | 21 | 24 |
| waves on the shore sounds | 0.97 | 0.3 | 9263 | 25 | 97 |
| what causes sound waves to echo | 0.63 | 0.5 | 4584 | 31 | 76 |
| which waves are used in sonography | 1.07 | 0.6 | 4992 | 34 | 73 |
| describe what the echo sounds like | 1.5 | 0.3 | 9229 | 34 | 57 |
| sound of an echo | 0.02 | 0.2 | 3911 | 16 | 33 |
| ocean waves sounds for studying | 0.13 | 0.4 | 4164 | 31 | 81 |
| waves on a beach sound | 0.02 | 0.6 | 62 | 22 | 11 |
| what are echo-sounding devices | 1.34 | 0.6 | 2361 | 30 | 61 |
