Answer:
Im sorry, but what are the options? We can't read your mind!
Explanation:
Workers formed labor unions because they wanted better pay, better working conditions, and benefits for their labor.
Answer: D
A catalyst is a substance that alters the reaction and doesn't involve in the reaction.So if the Manganese was a catalyst the mass would not have decreased,it would just continue aletring the reaction until its used up.
The Manganese is not acting as a catalyst
B. to support the industrial growth of the northern region of the United States