Explain how the environment and economy has impacted because of coronavirus

Corona Virus is helping the environment because people aren't constantly driving around and polluting the air. The economy, however, is dropping due to people not working and not making money and therefore, not spending as much money.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.