If an elevation of -100 meters below sea level, what does an elevation of zero mean?

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F. a fair coin is thrown in the air four times. if the coin lands with the head up on the first three tosses, what is the probability that the coin will land with the head up on the fourth toss? a. 0 b. 1/16 c. 1/8 d. 1/2

What is the domain of the step function f(x)=[2x]-1?