Urgent iReceivables Challenge Questions

  Question 1 - Is there a way to set the need to answer a second challenge question based on the repsonse to the first challenge Qeustion?  

My client has two customer types.  If the customer is of the second type - they must answer a second question.  How do I achieve this?

Question 2 - My clients needs to ensure the anonymouse user is actually the customer on the invoice (in case they enter the wrong invoice number). I need to give them a challenge question that will match the invoice even though they are not registering? 

 How do I do this?