Capital gain tax

Hello all.  I have the following enquiry which please help me with answers.

In 2009 I gave my sister some amount to purchase a land  in her namewhich was divided into plots and a few of them sold already,  Now I want the balance area to be totally sold out to a third party.  Following are my queries:

1. If I take part of the land as a gift from my sister, what will be the effect on sales.

2. If I sell the entire property and give my sister's share to her, what will be the Capital Gain Tax amount for both of us?

3.  If my sister is receiving a sizeable amount from me, how could she show the source of income?

4.  I am an NRI and I want to minimize the Tax amount payable both for my sister and myself.  How could I do it?

Thanks for your replies and advices.