The up and down movements of a liquid or gas are called
a. radiation
b. conduction
c. convection

Which statement is true for light passing into a medium that is more optically dense than the first medium through which it past

According to social exchange theory, altruistic behaviors benefit the individual who performs them. t/f

The focal length of a relaxed human eye is approximately 1.7 cm. when we focus our eyes on a close up object, we can change the refractive power of the eye by about 16 diopters. (a) does the refractive power of our eyes increase or decrease by 16 diopters when we focus closely? explain. (b) calculate the focal length of the eye when we focus closely.