Constitution of India and income tax.

This lecture shall answer following questions?
1. Do you know from which document Govt. derives power to levy taxes?
2. Do you know which Govt. has the power to levy tax on income?
3. Everyone knows Govt. can levy taxes only by making law. But which article of the constitution gives power to do so?
4. Do you know whether Central Govt has the power to levy taxes on agricultural income?
5. Which schedule of the Constitution divides the power to make law between Central Govt. and State Govt.?