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.
No. Unlike fish, whales and dolphins move their fins up and down when swimming. Think of the fin's motion as being related to the spine's motion. A fish's tail fin moves fro â¦ m side to side because it moves its entire spine from side to side when swimming.