Introduced species are very beneficial to ecosystems when they are brought into them. true or false? i say false

they can be true, it just depends on the variables of  the ecosystems

Generally speaking, it is mainly based on how they're introduced. If they are intentionally introduced by scientists, then yes, it's beneficial. However, if it's unintentionally introduced, it is considered an invasive species. Invasive species are not beneficial. 

To summarize: If intentional, true. If unintentional, false.

It should be cryosphere and hydrosphere

Lacking something of the ozone layer