1. the illuminance on a surface is 6 lux and the surface is 4 meters from the light source. what is the intensity of the source?
a. 96 candelas b. 72 candelas c. 24 candelas

2. which of the following is accurate in describing converging and diverging lenses?
a. both of these types of lenses have the ability to produce upright images.
b. diverging lenses will produce images behind the lens, and converging lenses will produce images in front of the lens.
c. both of these types of lenses have the ability to produce real images.
d. parallel rays converge into a single point at the focal point of a diverging lens, whereas parallel rays diverge at the focal point of a converging lens and spread out.

3. the light intensity of a source is 100 candelas. the illuminance on a surface is 4 lux. how far is the surface from the source?
a. 4 meters b. 6 meters c. 5 meters d. 7 meters