How many questions can we have on the quiz?

2.  How many questions can we have on the quiz? (is there a limit?)

As far as I know there is not a limit, when you open the form in the Quiz app you get all the fields that you have added to your form, all the fields can be used in the app, and there is not a fields limit in the Form Builder so far, so you may add the fields that you need to your form and you should be able to use them in the Quiz app.