Our analysis of production and cost begins with a period economists call the short. run. Theshort run in this microeconomic context is a planning period over which the. managers of a firm must consider one or more of their factors of production as fixed.
Sharks have two sets of paired fins on the sides of their body, in the same general position as the main wings and horizontal tail wings of a plane. The shark can position these fins at different angles, changing the path of the water moving around them.
Sharks are part of a family of fishes known as cartilage fishes. They have no bones in their bodies, only cartilage, like the soft flexible tissue in the end of your nose. Rays are also a member of this group. In fact, rays are actually nothing more than flattened out sharks. They are the birds of the sea.