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1) A fast spaceship is traveling with a speed of .80c. How fast would light travel from the headlights of the ship relative to a stationary observer?

I said the answer was .80c because there is no change, I mean on earth sure it would be different because of the distance it had to travel right?

2) How fast should a moving clock travel if its to be observed by a stationary observer as running at 1/2 its normal rate?

How do I solve for this? I assume I must calculate the normal rate and take 1/2 of that, correct? But how do I find that answer??

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