How do you set up a controlled experiment ?

Question

What's the purpose of a control group?
How many variables should a controlled experiment have?
What are the difference between observation and inferences?

I REALLY NEED HELP!!!!
PLEASE HELP ME !!!!

Answer 1

Check your book. Then post what you think are answers.

We'll be glad to check your answers.

Answer 2

Here is my answer for the first one

I set up a controlled experiment by getting all matirals that I need for my experiment and then using the scientific method to do my experiment.

Im working on the others

Answer 3

You described an experiment. What makes this experiment a "controlled experiment?"

http://www.biology-online.org/dictionary/Controlled_experiment

Answer 4

I got it covered already ;)