Geologist discovered that the largest coal deposits were formed around 300 million years ago. how did this observation support the theory of plate tectonics?

Around that time, "those regions were located in tropical climates" that were "partially submerged" on the coasts.

Explanation:

300 million years ago from now, the mean sea level was higher than what it is today. Hence, the oceans had a larger spread on the continental land. The tectonic plate movements decreased the mean sea levels drastically and the ocean waters thus shrunk back far backward horizontally. This backward descend of the ocean waters exposed the coal deposits.

May consider a group  g=({0,1},+)g=({0,1},+)where  ++  will work as the xor operator like we work in boolean algebra. note here, that ‘00’ and ‘11’ are not the usual 0 and 1 that we work with everyday. the elements are  called  ‘00’ and ‘11’ and  may not mean  zero (nothing) and one (single). ‘00’ is the identity for the given binary operator +, meaning that any element operated with ‘00’ gets us that element itself.  for a set  ss  in  g′g′  having more elements than just  {0,1}{0,1}  the values for  a+b∈sa+b∈s, such that  a∈s,b∈sa∈s,b∈s, have to be first defined, only then can you determine the value of  1+11+1. the answer could possibly have been  22  if oanswer is25,000

The process by weathered rock and mineral particles are removed from one area and transported elsewhere