Use the words below to fill in the gaps showing the path of air coming in and
out of the respiratory system (you will have to use each word twice).
trachea
alveoli
bronchioles
bronchi
bronchus
blood
mouth
mouth
air coming in
air coming out
cells

15. one purpose of the tread pattern on a tire is to a reduce tire wear. b. reduce traction c. allow water to flow away from the tire. d. look impressive.

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.

What are similarities and differences between refraction, reflection, diffraction and absorption?