The correct answer is Chemical. Because two substances are reacting and creating a new substance.
The nitrogenous bases Adenine form two hydrogen bonds with thymine and the cytosine form three hydrogen bonds with the guanine. Simply, A combines with T and G combines with the C. It is often called as a complementary base pairing because of each base pair bonds only with its specific complementary base partner in a DNA molecule.
The value because it could be worth a lot or a little
Predator
Because they are at the top they eat everything so when the arrows point towards them on the web it means they are essentially eating them because like a food web this organism is on top and the other prey are on the bottom