Brainliest asap but plz help me

looh. If you have ever heard an echo, you'll be familiar with the basic principle behind three similar technologies: radar, sonar and lidar. An echo is the reflection of sound waves off of some distant object.

Explanation:

Solar Panels and Radar

C                              A

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yellow fever and other tropical diseases

i confess that there are several parts of this constitution which i do not at present approve, but i am not sure i shall never approve them: for having lived long, i have experienced many instances of being obliged by better information or fuller consideration, to change opinions even on important subjects, which i once thought right, but found to be otherwise. it is therefore that the older i grow, the more apt i am to doubt my own judgment, and to pay more respect to the judgment of others.