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Changes can occur to physical properties of a substance, but the chemical composition of the substance remains the same.
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
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?? I don't know what these means
Answer:
Sound travels fastest through solids. This is because molecules in a solid medium are much closer together than those in a liquid or gas, allowing sound waves to travel more quickly through it. In fact, sound waves travel over 17 times faster through steel than through air.
Use a sandbag to hold it in place