Answer: Formaldehyde
Explanation:
The chemical agent that is carcinogenic in nature is Formaldehyde. It causes irritation in the living tissues and therefore should not be used as an antiseptic.
This can be used a chemical disinfectant which works by killing the harmful organisms by methylating enzymes and nucleic acid. This is toxic in nature and hence used as chemical disinfectant.
Answer is in a photo. I couldn't attach it here, but I uploaded it to a file hosting. link below! Good Luck!

That is a simile because you are saying you are like something. It means that you will fall down easily like a domino would if you knocked it.
Answer: circulatory system
Explanation:
Blood that return from the upper and lower parts of the body are deoxygenated hence they are transported to the heart for oxygenation. therefore blood enter the heart through vena cava ( the main vein) to the right auricles and it goes to the lower part of the heart which is the right ventricles which is more muscular. due to this blood is pumped from the right ventricles through pulmonary vein which pumps blood to the left ventricles through pulmonary artery and it is allowed to the left ventricles in the lower part of the heart and it pumped back in the body through the aorta( the main artery) .
Answer: B. Random mating
Explanation:
Random mating can be define as the individuals of one sex are potentially be the partners of the members of the opposite sex. It is also called as panmixia. Here, the chances of getting mates is certain. It occurs in large population. The physical and geographical barriers can prevent the random mating. In this allelic frequencies will not vary if the mating is conducted in a single population.