SAVE : It is nothing but saving the worksheet or any other page which is being currently edited and saved so that when the power goes off the data won't dissappear
SAVE AS : Giving the file name to...
Ecology is the study of interactions between biotic and abiotic factors in an environment. Biotic factors a living things (plants, animals...), and abiotic factors are nonliving things (soil, sun,...
You can save electricity by not buying stuff that uses more electricity. For example, an old style TV uses a fraction of the power of wide screen plasma TV. So first, keep your old TV, and second if...
We are not capable, as humans, to save or not save the Earth. We should be more concerned about saving ourselves. The Earth will exist for many more hundreds of millions of years with or without us.