Let vb be the velocity of the motorboat and let vs be the velocity of the stream.
We know that when she drives upstream the velocity is 8 m/s, in this scenario the velocities point in opposite directions, then we have the equations:

When she drives downstream the velocites point in the same direction then we have the equation:

hence we have the system of equations:

Solving the first equation for the velocity of the boat we have:

Plugging this in the second equation we have:

Therefore, the velocity of the stream is 2 m/s
Fluids are liquid or gases
different particles make up fluids and are constantly bouncing in a high random motion
Answer:
7 units, north
Explanation:
This is a problem of vector subtraction. We have:
- Vector A: magnitude 2 units, direction to the north
- Vector B: magnitude 5 units, direction to the south
If we take the north as positive direction, we can write

Since we want to find
(vector subtraction), we have to change the sign of B, so we find:

And the positive sign means the direction is north.