It was first detected by Robert Wilson and Arno Penzias.
Okay so we have gateway drugs, and over the counter drugs. There are more drugs but I'm afraid I don't have enough space. Gateway drugs are the worst, they are what start people off. say you had a friend that took marijuana and then went up to meth. they started off on marijuana, the gateway drug, they got so used to it that it didn't affect them anymore so they up graded. Drugs are always serious not matter the dose you take. I hope this helped
An independent variable is a variable that can stand by itself. It can be predefined or ultimately just stand alone.
