Unit 7 Contents

1. Describe how Arti and Jessie can measure the area of the spots they made.
1. What are the two main variables in the lab?
2. Which variable is the manipulated variable?
3. Which variable is the responding variable?
3. What variables should be held fixed so that Arti and Jessie can see how changing the number of drops affects the area of the spots?
4. Why is it a good idea to make more than one trial?

5. Design a lab to find out what happens to the area if you change the number of drops of water used to make the spot. Draw a picture of your plan.
1. Label the variables in your picture.
2. Choose values for the number of drops. (You may choose 1, 2, and 4 drops as Arti and Jessie did, or you may choose other values.)

You and your partner(s) will work together to collect and record data using the Three-Column Data Table on the Spreading Out Lab pages in the Student Activity Book. Discuss the following before you begin:

1. How many trials will you need to make? That is, how many times will you make a spot for each number of drops?
2. How will you organize your data in a data table?
3. What unit of measure will you use when finding the area?
4. How can you check for mistakes in dropping the water to make the spots?
5. How will you check to make sure your data is reasonable?
7. Work with your partner(s) to collect and record your data. Will you use the mean or median value to average your data? Explain your thinking.