The lungs have no skeletal muscles of their own. The work of breathing is done by the diaphragm, the muscles between the ribs (intercostal muscles), the muscles in the neck, and the abdominal muscles.
Answer:
Pressure is simply the force experienced by an object divided by the area of the surface on which the force acts. Note that the force here is the force acting perpendicular to the surface. The unit for pressure is the pascal, Pa.
Explanation:
D. Water is polar-convalently bonded, not by van der Waal forces.