Tax on liquid mutual funds

Hi, I have a small query as mentioned below.

1. My income is not taxable.

2. I want to invest in liquid mutual funds. Some investment will be of more then 1 year & some will be of less then a year.

3. What will be the tax effect for investments of less then a year & more then a year.

4. As for long term I understand that 10% without index & 20% with index. Now. as my income is below taxable limit, do I still have to count 10% or 20% tax, as applicable & pay it accordingly or will it be added to my income & there after as my income is below tax limit, so I do not have to pay tax at all??

Plz. advice. Thank you.