a person who has red rimmed eyes and a runny nose but does not suffer from allergies or have a cold shows the warning sign of drug abuse

relationship between pressure and air volume and led to the understanding of how respiration works; i believe this is the correct answer ; /// good luck

tell their parents and make sure she gets from a counselor or therapist. be supportive and be there for her. be a kind and good friend. spend time with her to make her feel like she's not alone. i'm not a professional but i really hope they stays strong.