✔ 最佳答案
1. No.
2. Yes. Regardless of your responsibility (no responsibility) in this case, when B approaches you in attempt to collect, it is B's belief that you are liable for the payment.
In other word, when B can't collect from A and decides to sue, you will be named as a defendant as well (even B has no case against you).
As soon as A fails to pay B, it is only a matter of time than you and A will be sued (even you are not liable in this case).
So in this case, it is better to start preparing document relating to the work done by A, invoices, payment, etc. so that you can better protect yourself.