Draw a free body diagram to show which forces act in the x and y directions. The x component equation is σfx = 0. The σfx being all the forces acting in the x direction.
Action and reaction are equal in magnitude and opposite direction by they don't balance each other because they don't occur on the same body. Action is involved on one body and reaction is involved on another body.
Hope you understood...
Answer:
The human ear is most sensitive to sounds in the range of 2000 to 3000 Hz
continents, paleoclimate indicators, truncated geologic features, and fossils:D