The answer is: b. The Soviet Union fell apart
Before Gorbachev's reforms exist, several territories in soviet union was united under one principle of communism.
When the Gorbachev's reforms were created, the soviet union started to adopt some of democratic and free market value that adopted by countries in western hemisphere.
When this happen, the bind that united territories in the soviet union no longer exist. This became one of the factors that caused the soviet union to fell apart.
Answer:
Electromagnetic waves are created by a charged particle that generates an electric field. The electric field creates a magnetic field. As the charged particle moves the electric field and magnetic field keep changing, which causes the wave to move.
Explanation:
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I am pretty sure it's four. I looked it up, and I have a book I just looked through. Sorry if it's wrong! Have a good rest of 2016!