Why does the chemical reaction seen here obey the law of conservation of matter?

Which expression allows you to determine the mechanical advantage of an inclined plane? a. height of plane / input force b. length of plane / input force c. length of plane / height of plane d. height of plane / length of plane

The passage that directs air to the lungs is called a. diaphragm. b. larynx. c. bronchi. d. pharynx.

See the attachment and solve question 5th