By he NIH trying a new drug to help reduce pain associated with sickle-cell anemia, it's an example of an "experiment".
An experiment involves a hypothesis (an educated guess as to what's going to happen) and trying out the hypothesis and finding the solution.
Answer:
Risk factors are internal characteristics or external situations that increase the likelihood of a mental health problem or illness. These can be offset by protective factors, which tend to decrease the chances of mental health difficulties. Risk factors do not cause illness.
Yes, everything has an expiration date. And since that is food you are asking about I advise you not to eat expired food even if it may seem safe, it is the best thing to do to protect you.
