Finish build triggers and build properties/pre-test commit.

Suppose I have 2 builds A and B.  B has a 'Finish Build Trigger" on A.  What happens when...

     1)  Someone does a personal build on A - Does B execute and if so is it personal too?  What I really need tp know - is the "build.is.personal" property set for build B too?
     2)  Someone does a "pre-test commit" on build A -  Does it run build B too?  Does it wait until build B is done before commit?  And if build A is successful but build B is not - does it commit the source?