If your floor really needs more than that, consider a low-cost alternative to refinishing: Apply a fresh topcoat of nonyellowing polyurethane, found in the flooring section of a home improvement store. Be sure to very lightly sand the floors with a pole sander and fine-grit sandpaper.
There are 440 different species of sharks in the world today classified into eight different orders described below with some examples of known sharks species for each group.
There is over 350 species of sharks and more are being reported all the time, how ever there are also roughly 400 species of rays which are close relatives to the sharks. well my point is that each shark has its own speed if you would like to post a different question a little more specific i would gladly answer it!