The answer is the first option. Gas burning in an engine is an example of a chemical change. Chemical change is a change where the substance changes in identity or form new substances after undergoing a process. In this case, the gas reacts with oxygen forming combustion products, commonly carbon dioxide and water.
B. Low blood pressure and drooling. If the user is tranquilized, he would not be able to hinder the production of saliva, leading to drooling. And if the victim was tranquilized, his heart would slow down, not speed up, resulting in a lower blood pressure.
Adaptation actually and also following control measures on how to avoid it from happening
Q = m x c x ΔT
2500 = 0.135 x C x 80.5
2500 = 10.8765 x C
C = 230.043 J/Kg.K
hope this helps