a.It is not possible for a candidate to have all the experience an employer requires. Even if you match yourself up to the expectations on technical front, there will be some difference in the work environment. And, it is absolutely fine. The best way to deal with this question is to analyse the requirements of the position well and match your skills as close to them as possible. If something is still left untouched, offer your quick grasping power and ability to learn quickly as a solution & back it up with an example from the past.