Why is it a good idea to have a carbon monoxide detector in the home?
to keep parents and children from suffocating
to avoid poisoning by a buildup of co gas
to warn members of the household of smoke from a fire
nextreset

It is a good idea because it helps to detect if there is too much carbon monoxide in the house. If there is too much, it can be poisonous and the detector will let you know. this answer would be TO AVOID POISONING BY A BUILDUP OF CO GAS. 
btw, is this platoweb? just curious.

Heyyy! drugs are not good for u. and u should know that! it can injure you or hurt u! drugs itself sounds dangerous! i'm pretty sure u heard many stories about the danger of drugs! even if u are addicted or just want to, pls don't do it! it's harmful even though maybe u don't realize it. until u realize it, it's going to be too late, and i don't want that to happen to u or to anyone. drugs shouldn't be your top priority, just think about it, why do u want to use drugs? u can do so many other things that can relive u, or things u like to do. i might not get what situation u are in, but drugs can't be the thing on your mind all the time, what if the ppl that cares about u gets hurt because, one day they get a call that u are in a hospital; injured or they can have a knock on there door telling them that u past away or something happened. it's not cool and upsetting, obviously i'm not someone who can force u to not do anything u want to do, but pls keep in mind, always think about the people who cares about u, and if u see a child younger than u by a lot, or just younger, u would tell them to not do drugs(maybe) if u do tell them that, u realize it's bad for them, which means u abounds do it either bc its bad. no matter the age, u shouldn't be doing stuff that would hurt u, bottom line is, i can't tell u what to do, u do u, but i'm younger than u, and just want to say pls don't get hurt.