If you want to dry your plate faster use a clean cloth.
It grows faster on a wet substance because its spores reproduce.
perhaps because it's wet
Wet will mold faster as the moisture accelerates the growth (especially in a dark environment)
Yes. A wet animal will cool faster than a dry animal. The evaporation of the water removes heat from the body and cools it.
If the wet cloth is left in the sun it will dry faster as sun's heat helps water to evaporate. And the air helps in taking away the humidity around the wet cloth.