Your chest may hurt because you might have something going on your body.
You might have a itchy throat or you might be sick.
True, all of these could be symptoms of stress
Iodine solution is used to test leaves for the presence of starch. You need to: heat a plant leaf in boiling water for 30 seconds (this stops its chemical reactions) heat it in boiling ethanol for a few minutes (this removes most of its colour)
Define “the following” so we can answer the question
Substance abuse such as drugs, alcohol and tobacco, family problems such as domestic violence and abuse, social problems such as peer pressure, bullying, and exclusion, and so many other environmental reasons, but substance abuse, family dysfunction and social problems are the common reasons why.