20 is the Number of Neutrons of potassium.
Answer:
The DNA in prokaryotes is contained in a central area of the cell called the nucleoid, which is not surrounded by a nuclear membrane. Many prokaryotes also carry small, circular DNA molecules called plasmids, which are distinct from the chromosomal DNA and can provide genetic advantages in specific environments.
Explanation:
20. The answer is 1 (Precambrian)
21. The answer is 4 (Pennsylvanian)
22. The answer is 2 (Bony Fishes, Dinosaurs, and Mammals)
23. The answer is 2 (Reptiles)
<span>C6H12O6 + 6O2 ==> 6CO2 + 6H2O
</span><span> This chemical reactions proves the fact that the products of photosynthesis are reactants of respiration
hope it helps</span>
