Answer - It is a Great Concern because microbes such as a hydra can consume some of that mercury which then a shrimp can consume that microbes which then transfer into the mouth of a trout which then when humans fish they consume the fish which later we get Mercury poisoning.
Reasoning - There are more concern but these are a few and some reasoning.
Explanation: I think camouflage method or a design that scares away predators.
It’s 100 percent purple as PP purple flowering plants are dominant and pp is recessive
The phenomenon is called an equinox. More specifically when it is September it is called the autumnal equinox ,and when it is March it is called the vernal equinox. Hope this helped!