Issues with switching between VS versions

Hey I have two question, I’ll start with the the first one how exactly can I switch between VS version in UE? I’m using version 4.9 and every time I create a C++ class it’s opening 2013 but I want it to open 2015. I checked the drop down menu in editor preferences and it’s only showing Visual studio…no VS 2013, 2015, etc. My second question is how can I check which version a few C++ scripts are valid in? I have a folder containing scripts that I’m trying to import into my project but they aren’t showing up in the content browser. I tried importing in the VS program, exiting the project, generating visual studio project files and then reopening the project and they still aren’t coming up.