problem 1: What do you mean by lentic systems? What are various zones in which a lake can be divided on the basis of the light penetration?
problem 2: Describe the seasonal changes which occur in the thermal structure of a lake?
problem 3: Give a detail explanation of chemical properties of lakes.
problem 4: What are various phases in the course of a river?
problem 5: Describe the relief features of ocean bottom with the help of a suitable diagram.
problem 6: What are various types of zones in the marine water?
problem 7: What do you mean by the term salinity? How does it differ spatially in the oceans?