During which geologic era was there widespread laying down of sediments which later formed coal deposits? mesozoic cenozoic paleozoic cambrian

The answer is Paleozoic.

Explanation:

The last time of the Paleozoic was the Permian Period, which started 299 million years back and wrapped up 251 million years prior. This period would end with the biggest mass eradication ever: the Permian termination. Before the finish of the Paleozoic, cycads, glossopterids, crude conifers, and plants were spreading over the scene. The Permian annihilation, 244 million years back, crushed the marine biota: classify and rugose corals, blastoid echinoderms, graptolites, and most crinoids vanished, as did the remainder of the trilobites.

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