Chemical composition of the pesticide.
= pestcides and fertilizers are bad and ruin their crops =
Yes, cats are known to hunt and kill frogs.
no, not tree frogs, but some other frogs can be like that
No, snails don't kill frogs they actual help frogs by eating harmful bacteria.
Yes, chlorine can be harmful to frogs and can potentially kill them if they are exposed to high levels of it in their environment.
Most substances foreign to frogs are harmful or lethal.
They get protected from the pests which are threatening them.
Wild animals
sometimes
you can not kill rocks there not alive
There skin will kill you
they kill themselves by drowning them