agriculture Land

I have purchase agriculture land in 2014 of 13bigha.out of it I sold 8 bigha agriculture land in 2016. From remaining 5bigha , I sold 3 plot of each 2000sqft.My questions are

1) Tax liabilities on sold plots and whose liabilities?
2) If I want to sale remaining agriculture land in partition to buyer than what is tax liabilities & from which side (buyer or seller).
3) Applicability of tax on whole 5 bigha on sales time or area in which is sold it to be sold.

Warm Regards,
Pavan Kumar