An example of a biologically formed sedimentary rock would be

An example of a biologically formed sedimentary rock would be limestone.

Explanation:

Biologic sedimentary rocks form when large numbers of living things die, pile up, and are compressed and cemented to form rock. Accumulated carbon-rich plant material may form coal. Deposits made mostly of animal shells may form limestone, coquina, or chert.

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explanation:

the atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons.

grav forces affect all objects magnetic forces affect magnetic objects and electric currents