the answer is (A) the movement of the magnet relative to the coil
Answer:
The resultant velocity is <u>169.71 km/h at angle of 45° measured clockwise with the x-axis</u> or the east-west line.
Explanation:
Considering west direction along negative x-axis and north direction along positive y-axis
Given:
The car travels at a speed of 120 km/h in the west direction.
The car then travels at the same speed in the north direction.
Now, considering the given directions, the velocities are given as:
Velocity in west direction is, 
Velocity in north direction is, 
Now, since
are perpendicular to each other, their resultant magnitude is given as:

Plug in the given values and solve for the magnitude of the resultant.This gives,

Let the angle made by the resultant be 'x' degree with the east-west line or the x-axis.
So, the direction is given as:

Therefore, the resultant velocity is 169.71 km/h at angle of 45° measured clockwise with the x-axis or the east-west line.
Yes, yes, we know all of that. It certainly took you long enough to
get around to asking your question.
If
a = (14, 10.5, 0)
and
b = (4.62, 9.45, 0) ,
then, to begin with, neither vector has a z-component, and they
both lie in the x-y plane.
Their dot-product a · b = (14 x 4.62) + (10.5 x 9.45) =
(64.68) + (99.225) = 163.905 (scalar)
I feel I earned your generous 5 points just reading your treatise and
finding your question (in the last line). I shall cherish every one of them.
Velocity is a vector quantity. A vector quantity has both a magnitude and a direction. Speed only has a magnitude, but no direction. Velocity has both.