Answer:
Stroke is the correct answer
<span>A) x = 41t
The classic equation for distance is velocity multiplied by time. And unfortunately, all of your available options have the form of that equation. In fact, the only difference between any of the equations is what looks to be velocity. And in order to solve the problem initially, you need to divide the velocity vector into a vertical velocity vector and a horizontal velocity vector. And the horizontal velocity vector is simply the cosine of the angle multiplied by the total velocity. So
H = 120*cos(70) = 120*0.34202 = 41.04242
So the horizontal velocity is about 41 m/s. Looking at the available options, only "A" even comes close.</span>
Wavelength times frequency = speed of light
7.5E14 x wavelength = 300,000 m/s
Wavelength in meters = 300,000 divided by 7.5E14
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