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
because light through the mineral travels through Only refraction where as at the edgee it travels through refraction as well as diffraction...so more dispersion of light so more clear to see