Why oils of different viscosity are used in different seasons?

________ is a systematic cultivation of different crops in a proper sequence in different seasons on the same land.

What are the different crop seasons?

Why seeds are in different shapes?

Why are strings of different thicknesses and different materials used in a sitar or violin?

Why the strings of different thickness and different materials are used in Sitar (Violin)?

What is difference between viscosity and friction?

A table showing the average quantity of urine in a person in two different seasons are given. Compare it. Do you agree with this table? State the reason for producing different Quantity in different season.