Yes, they are part of the food web and with out them animals would die.
they are helpful not harmful to plants
If it is harmful it will not survive long
Harmful: Winds can destroy structures. Helpful: Winds can power windmills.
If you need help I recommend you type in the specific question you need help with
yes they kill more harmless insects than harmful ones.
Helpful. They eat other smaller animals that overpopulate the jungle. So, in that way, yesss :)
mushrooms are helpful because they break down dead organisms and are "clean-up" the environment.
it can be helpful or harmful
sometimes they are helpful and harmful.
Sandpaper is both helpful and harmful.
It doesn't
due to human error