The radio waves are electromagnetic wave, so it travels with velocity of light i.e
.
We can use the relation between frequency, wavelength and speed as

Here c is speed of light,
is wavelength and f is frequency and its value is given 99.90 FM, it is actually in megahertz (i.e 99.90 MHz).
Therefore,
.
Thus, the broadcast wavelength of the given radio station is 3.003 m.
Divide the change in speed by the time for the change.
However instead of crests and troughs, longitudinal waves have compressions and rarefactions. Compression. A compression is a region in a longitudinal wave where the particles are closest together. Rarefaction. A rarefaction is a region in a longitudinal wave where the particles are furthest apart.
when a glacier came through the Bronx approximately 240,000 years ago it blocked part of the original path of the Bronx river and subsequently reshaped and modified the path of the river over the past 200 years the rivers course has been altered dramatically by human impact and industry.
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