Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Sajan sarthak
Profile section of fold is that section which is perpendicular to foldaxis. So here cylindrical fold is a best possible answer which maintains the constant profile relationship.. concentric fold is a type of cylindrical fold . concertina fold is kink like structure may or may not maintain the constant nature. figure below for better understanding.