Restore a deleted class

QUESTION
I went in and deleted my class from last year and created my class for
this year.   However, when I did that I lost all of my custom tests!
I spent a lot of time creating those tests.  I didn't know they were
associated with my old class only. I thought they were associated with
me.
My first question:  Is there a way to get those custom quizzes back?
My second question: If there isn't a way to get them back, is there a way
you could make it in the future so that quizzes can be used in more
than one class and won't be deleted when the class is deleted?
(Perhaps a way to export the saved quizzes so they could be imported
back in for another class?

ANSWER
You can restore the deleted class.
Click the "New Class" link and instead of entering new students,
choose "Import".  One of the options is to restore a previously
deleted class.  This will restore all students, grades, and also
exams.  I suggest copying all the exams for the new class (click the
tests and then click the "Share" button to make a copy for the new
class).  When you're finished copying exams, its probably safe to
delete the old class again.