Answer:
hydroshpere and biosphere
Explanation:
it contains
hydrosphere: cleaning of water
biosphere: helps plants and animals
Answer:
I personally think that all the methods could potentailly work but I would have to go with "A" as usaully GPS's are used as they are more simple and easier to have in a collar, as radio technology is probably the number one most used by people such as scientists
I would consult your parents if you think you might have adhd but me being a person that has adhd I would say if you are very jittery and get side tracked very easily then those are some signs however if you comment why you think you might have adhd I can help you out :)