7. By studying folds, faults, and intrusions in rocks, scientists can determine A) the age of rocks in years
B) the order of past earth events
C) the depth of the ocean
D) if there is life on mars

A) the age of rocks in years

Explanation:

Examples of features that cut through rock layers are faults and intrusions. ... This theory helps geologists to assess the relative ages and occurrences that disrupted the rock layers. Two types of events that disrupt rock layers are folding and tilting.

The layers of sedimentary rocks are generally studied by scientists to assess the relative age of rocks.

"a scientist studying a whale and its surroundings would need to understand the structure of atoms in case something was negatively affecting the whale or its surroundings."

explanation:

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