Which of the following statements is true? the decca navigation system is used today by the u. s. coast guard. sonar was developed during world war i to track the location of underwater mines. seismic profiling uses high frequency radio waves to map the surface of the ocean floor. all of the above. none of the above.

None of the above.

Explanation:

The Decca system was discontinued in 2001. Loran-C replaced the Decca navigation system which was more accurate. Loran-C uses low frequency radio waves.

SONAR (sound navigation ranging) was developed in World War I for threats like submarines.

Seismic profiling uses frequencies lower than 3 to 30 Hz which is not considered as high frequency.

none of the above

Explanation:

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