A: In the middle to high latitudes on a dark night an aurora or the curtain of light hangs down from the sky. This curtain is local, several hundred kilometer high, several thousand kilometer long but less than 1 km thick. R: Electrons and protons trapped in the helical terrestiral magnetic field collide with atomsand molecules of air, causing that air to emit light.

A: In the middle to high latitudes on a dark night an aurora or the cu

1.	A: In the middle to high latitudes on a dark night an aurora or the curtain of light hangs down from the sky. This curtain is local, several hundred kilometer high, several thousand kilometer long but less than 1 km thick. R: Electrons and protons trapped in the helical terrestiral magnetic field collide with atomsand molecules of air, causing that air to emit light.
Answer» If both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark (1) If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark 2. If assertion is true STATEMENT but Reason is FALSE, then mark (3) If both Assertion and Reason are false statements, then mark (4) Answer :A

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