Answer:
the layer of the earth's atmosphere that contains a high concentration of ions and free electrons and is able to reflect radio waves. It lies above the mesosphere and extends from about 50 to 600 miles above the earth's surface.
Explanation:
Commonly, genes from bacteria are inserted into a crop's chromosomes to produce pesticide substances to kill insects
For drought, I'm not fully sure, but Maize is a very drought resistant crop often introduced to communities which receive little rainfall. Maybe they take a gene from the maize crop and insert it into the chromosomes