They are dangerous to the environment because they have no natural competition. That being said they have nothing to keep their population in check, therefore, taking away food, and habits from all the other species. Thus, causing species to die out, which in turn ruins the food chain.
Third trimester. It doubles in mass at this time and continues to still grow and mature
True - by a majority, at least. This would be because when a young child is growing up, they need a surplus of attention. when not provided it will cause the development of self and brain, and so understanding of others, to be hindered. With little compassion and bad habits comes dislike from peers.
this event occurred at Chernobyl Nuclear Power Plant
hope this helps! - Jentri