Here's an explanation and graphs of a competitive market.

http://www2.harpercollege.edu/mhealy/eco212i/lectures/ch3-18.htm

1. Provide at least one example of a variable that affects the supply curve and at least one example of a variable that affects the demand curve.

2. Think of a product or service that you use in your everyday life or workplace. Describe how the supply or demand of this product might be changed.