The Richter scale doesn't measure quake damage (see: Mercalli Scale) which is dependent on a variety of factors including population at the epicentre, terrain, depth, etc.
The circulatory system works with the muscular system, the nervous system, and the digestive system. The heart is a muscle so it is part of the muscular system. Also the heart and lungs have nerves so it is also part of the nervous system.
The Human circulatory system is an organ system that is mainly concerned with transportation of nutrients, gases, blood cells and hormones throughout the body, through a network of blood vessels. It is also the main cooling as well as transportation system of the body. The RBCs carry nutrients and oxygen to the cells while the white blood cells in the circulatory system act as cleaners and start functioning whenever we are exposed to cold, infection or cut. The main components of circulatory systems are arteries and veins.