4. A rocklike copy of a plant, a feather, or a bone is a

FOSSIL

A rock-like copy of a plant,a feather,or a bone(natural things) is a FOSSIL

Explanation: Fossil can be defined as the preserved remains or trace or impression from a plant or animal that pre-existed in history or geological age,these remains are preserved in petrified form in the earth crust.

Fossils serves as the primary source of information about the history of life of a plant or animal on earth.

They are studied by archeologists.

The five types of fossils are; Carbon Fossils,Trace fossils, Body fossils, Molecular fossils and Pseudo fossils.

micro/nanoscale topography surface exhibits many prominent properties and is extensively employed in biomedical device, microfluidic device and energy device fabrication. additionally, the clinical applications of biomaterials can be largely expanded with of nanostructured surfaces.

the median of the data is 4.5.