If a string completes 500 vibrations in one second, what is its frequency?

Aboat radioed a distress call to a coast guard station. at the time of the call, a vector a from the station to the boat had a magnitude of 45.0 km and was directed 15.0° east of north. a vector from the station to the point where the boat was later found is = 30.0 km, 15.0° north of east. what are the components of the vector from the point where the distress call was made to point where the boat was found? in other words, what are the components of vector c = b - a?

The combining of light nuclei is called blank. blank as in not actually blank. you know what im tryin to say.

Place me with this question is my last question