The definition of an Olympic size swimming pool is 10 lanes each 2.5 meters wide, however to prevent the outside lanes being disadvantaged by having to compete with the waves bouncing off the sides of the pool only the middle 8 lanes are ever used.
FINA which is the world governing body for international swimming calls for a 50 Meter pool with 8 lanes. However movement is being created for having pools built with 10 lanes, with the outer 2 not being used for competition. (The waves created by swimmers bounces off the side walls and 'slows' down the swimmers in those lanes, thus an buffer is created by not using lanes 1 and 10 in competition). That said, if you are talking about size, Olympic generally refers to the length of the pool, not the number of lanes.
to col off
rain and acid wash
sweep it and put soap and water on a wash rag
Yes, a machine in a form of sensors judges the swimmers.
terpentine should do the trick
If all else fails, drain the pool, evict the alligators, wash off the algae residue, and start over.
They take a shower because their skin could dry out. Pool water is chemically treated, and these chemicals leave a residue on the skin which can damage it if not removed. Also, swimmers in particular sweat quite a bit while racing or practicing. That may be counterintuitive, but its no different than any other heavy exertion sport in that respect. This sweat leaves some residue also, even though the person was immersed in water. A quick rubdown in the shower (usually with soap) eliminates this sweaty residue.
No, adding chlorine directly to a pool while people are swimming is not safe. Swimmers should wait until the chlorine has dispersed and the water is safe before re-entering the pool.
Acid wash it with a presure sprayer.
All fiberglass has a final coating of gel coat, it could be marine gel coat, tooling gel coat, or swimming pool gel coat. Typically, swimming pool gel coat will last about 20 years before it loses effectivness. At that point, algae becomes able to "cling", the surface begins to stain, and the actual fiberglass becomes evident to swimmers, causing scratches. There is only one solution, lightly sand off the remaining gel coat, wash down the pool, apply one coat of vinyl ester resin, and roll-on 3 coats of swimming pool gel coat. The pool will be as good as new for another 20 years, provided the pool is properly cared for.