All the statements can be used to explain about Earth's magnetic field.
Earth's magnetic field is almost same to that of the bar magnet. The magnetic field of the earth occurs from its core. It has an inner core which is solid in nature. in the outer core, there is a motion of the liquid due to heat flow from the inner core to the core mantle boundary which proves that the outer core is liquid and moving. The Earth's core consists of iron and nickel as the Eddy currents in the iron and nickel liquid helps generating the Earth's magnetic field.
Hence, all the three statements are true and can be used to explain the Earth's magnetic field.
Oh your from the other question you made I just saw it LOL.
But heres the answer click the 3 dots on the question you made or you can ask a Moderator or Administrator to remove your question with a reason.
Answer:
(a) 
(b) 
Explanation:
<u>Electric Circuits</u>
Suppose we have a resistive-only electric circuit. The relation between the current I and the voltage V in a resistance R is given by the Ohm's law:
(a) The electromagnetic force of the battery is 
and its internal resistance is 
. Knowing the equivalent resistance of the headlights is 
, we can compute the current of the circuit by using the Kirchhoffs Voltage Law or KVL:
Solving for i
i=2.28\ A
The potential difference across the headlight bulbs is
(b) If the starter motor is operated, taking an additional 35 Amp from the battery, then the total load current is 2.28 A + 35 A = 37.28 A. Thus the output voltage of the battery, that is the voltage that the bulbs have is
The answer is B because if you use process of elimination, you find that A is invalid because Venus is the second planet. C is out because Mars is the 4th planet. D is out because we are nowhere near the Andromeda Galaxy. We are millions of light years away.
