Why does the midi system (sound system) have the widest range of frequencies?

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

Select the correct answer. what does the process of natural selection involve?