Answer:
B.
Explanation:
An allergic response is a hypersensitive immune reaction to a substance that normally is harmless or would not cause an immune response in everyone.
Answer: A steam engine is an external combustion engine (ECE) in which the fuel is combusted outside of the engine, unlike an internal combustion engine (ICE) in which fuel is combusted inside the engine. ECEs have a lower thermal efficiency, but carbon monoxide production is more readily regulated.
