Selection should include the

• use of cream or liquid developer
• appropriate strength of developer for the desired results (i.e., 10, 20, 30, 40, or 50).

Process/Skill Questions:

• When is a liquid developer used?
• When is a cream developer used?
• How is the strength of the developer determined?
• What is the most commonly used developer?
• What color categories require the use of a hydrogen peroxide developer?