Look at the following example and answer the questions:
Many argue that they cannot concentrate on work unless they have a cup of coffee. Others believe that caffeine intake is disruptive and will result in a poorer performance. A psychologist decided to investigate. He wanted to find out if caffeine intake affected people's performance on a memory test. Some participants had 2 cups of coffee, some a glass of water and some nothing to drink at all. He tested 30 people from a large office and divided them into 3 groups.

• How would you conduct the study?

• Make a possible hypothesis for this study

• Find two things in this example which indicate that this is an experiment

• What is an independent variable? Find it in this example

• What is a dependent variable? Find it in this example

• Who is in the experimental group and who is in the control group(s)?

• What are possible faults in this experiment?

• Explain why it is important to assign people randomly to groups