Answer:
The correct answer is option (D) there was a time in Pennsylvania history when dinosaur existed.
Explanation: A paleontologist discovers a rock slab on which the footprints of a Pennsylvania dinosaur are well preserved. This means that there was a time in Pennsylvania history when dinosaur existed in this area. Here fossil is a fragment of rock on which the footprints of dinosaur is present.
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As Earth orbits the Sun, this same principle is used by astronomers to determine the distance to nearby stars. ... Parallax is the first "inch" on the yardstick with which astronomers measure distances even further to objects.
Answer:
B. Sea levels will rise , causing floods