2 - Where do I put the Authorize.net widget?

2 - Where do I put the Authorize.net widget?

         a - at the end of the entire form?

         b - just prior to the submit button?

There's really no specific place that you have to place the Payment Integration since you can actually place it wherever you want depending on the type of form you are building. Normally though, in most cases it is best to have it at the end as this makes the most sense since that should be the last thing you see before you finish the form and submit it.