Answer:
A.
Explanation:
All the arrows align to the point right
Wavelength = (speed) / (frequency)
Wavelength = (300 thousand km per second) / (10.5 billion per second)
Wavelength = (300 / 10.5) (thousand km per second) / (billion per second)
Wavelength = (28.57) (million meters / second) / (thousand million / second)
Wavelength = (28.57) (meters / second) / (thousand / second)
Wavelength = (28.57) (meters / thousand)
<em>Wavelength = (28.57) (millimeters) </em>
Differentiate the components of position to get the corresponding components of velocity :


At <em>t</em> = 5.0 s, the particle has velocity


The speed at this time is the magnitude of the velocity :

The direction of motion at this time is the angle
that the velocity vector makes with the positive <em>x</em>-axis, such that
