Different versions of ssrs reports

I have the following questions about a few different versions of ssrs reports:

  1. In my company, one of the report servers is version 2012. The rest of the report servers are newer.
    My question can I place newer versions of ssrs reports on a report server that runs ssrs 2012 only?
    If so, what version of visual studio can I use? Can I use Visual studio 2013 and/or a new version?

  2. Can I keep both Visusl Studio 2010 and a newer version of Visual Studio like 2013 on my workstation? If so, are there any problems that I need to be aware of? If not, can you tell me why I cannot keep both versions of Visual studio to write ssrs reports on my workstation?

I'm not sure on #1 but you can certainly run every release of Visual Studio from 2010 upwards in a side-by-side configuration without issue - well apart from all the disk space it uses! :wink:

Thank you for your answer on question #2.
Does anyone have answer for my question #1?