2. All lasers must have which of the following a medium a light source both of the above none of the above
3. How many classifications of lasers are there.? 3 2 4 none of the above
4. Which part of the human body is most vulnerable to laser radiation? skin eye brain ears
5. What color is laser light? always red red or green any color depending on what type of medium is used none of the above
6. Which of these materials are acceptable mediums? gases solids liquids all of the above