L2 Visa help needed for Women - URGENT!!!?

[dholariya_b_r]

I would like to know the answers of few L2 visa questions for spouse.
My Visa L1 got approved, Now I am applying for my daughter(5 year ) and wife. We got the early PA date at Chennai for L2 than Mumbai but in DS160 it is Mumbai.

1. Why do you have to go to the US?

2. How long will be stay in US? ( 1 year is ok?)

3. Why have select PA at Chennai not Mumbai(DS160 is Mumbai)?