What are two examples where portions of the geologic time scale are compared to a common object?

Relative age is the age of a rock layer (or the fossils it contains) compared to other layers. ... Absolute age is the numeric age of a layer of rocks or fossils. Absolute age can be determined by using radiometric dating.

Explanation:

An eon, the largest division of the geologic time scale, spans hundreds to thousands of millions of years. Geologists generally agree that there are two major eons: the Precambrian eon and the Phanerozoic eon.

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

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bioteacher101