Assertion: ocean's depth | /r/HasProperty | determined
Facets:
value: by multiplying one-half
type: MANNER
Source sentences:
text: They operate on the principle that the depth (or distance) of the seafloor can be determined by multiplying one-half the elapsed time between a downgoing acoustic pulse and its echo by the speed of sound in seawater (about 1,500 metres [4,900 feet] per second).