Which of the following statements is true for a system at chemical equilibrium?

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Abacterium was found to contain a sequence of atcgggatcct in its genome. a few generations later, the sequence was found to be atcatcct. what type of mutation caused this change in the bacteria? a. duplication b. insertion c. inversion d. translocation

Afish fossil is found in a rock. a foot bone and tooth are found in an older layer of the same rock. what can scientists learn from the rock? a) the area changed from land to water. b) the area changed from water to land. c) the area has always been land. d) the area was once an ocean.