1. Is A. at the poles because thats where the magnetic field is going out then coming back into the earth to produce the magnetic field.
2. Again its A. because the compass needle is attracted to " north " which is magnetic south. It does this because opposites attract.
3. This one would be B. Because if the magnets were being repelled the magnetic field lines would look like there was a line that the field hit and bounced off of it.
4. This answer is A. the magnetite helps them migrate so they know which way is north and which way is south.
5. This answer is A. Because without the domains there wouldn't be poles on the magnetic object. <span />
Need a picture of the problem
Answer:
C) 90 degrees
Explanation:
If we could have an imaginative illustration about what the question is all about.
We could think of the velocity of the river (V_r cosθ) as a horizontal component and the velocity of the boat (V_b sinθ) as the vertical component.
So the velocity of the boat V_b = 2.2 m/s; &
the velocity of the river V_r = 1.1 m/s
∴
The minimum time (which is the shortest time) required for the boat to cross the river is θ = 90°
the time require is:


t = 43.18 sec