DR-40X mixing and bouncing options

[Bambi]

Hello, I'm thinking of buying the DR-40X recorder, but have a couple of questions about the mixing options. My idea is to record different tracks independently, not at the same time. I'd like to record for example 2 stereo tracks and 1 or 2 mono tracks. My doubts are the following:

1) Can I mix 1 stereo track together with a mono track? Will the resultant file be mono or stereo?

2) Can I use that resultant file to mix it with another stereo track? (Something like doing a bounce)