1. Using the scattering properties of the atmosphere explain why under clear sky condition the sky is blue. Why the sun looks red at the time of sunset or sun-rise?

2. Why X-ray is used for medical examination? Using radiation law No. 3, explain why as a piece of iron is heated, the color of the iron begins with dark red, then changes to red, to yellow to white.

3. Describe how one may use absorptance and transmittance of a matter in remote sensing.

4. Use Figures 2.4 and 2.5 as references, answer the following questions:

5. Can we use 6-7 Ám to observe the atmosphere?

6. Can we use 0.8-1.0 Ám to observe under water materials such as plankaton?

7. Which spectral regions should be used to observe water content in the atmosphere? What about water content in vegetation?