The circulatory system helps the excretory and digestive system do their jobs because the waste from the blood in the circulatory system is eliminated from the body through the excretory system, and the nutrients absorbed by the digestive system are transported through the blood.
Binary fission is the most common form of reproduction in protozoa!
A=T= 40%....so together this is 80% of the DNA.
That leaves 20% to be C+G...so each is 10%. A is the answer.
