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)
Mayank vedwal Vedwal Best Answer
Sm-Nd method is used for dating archean rocks because the half life of Sm-Nd is 100by and also Sm and Nd are incompatible elements which prefer melt phase and they were in sufficient amount in the bulk silicate earth before the differentiation of earth's mantle ( Archean time) .