C-01-Q073mediumsingle_mcqJn={1,2,3,…,n}J_n = \{1, 2, 3, \ldots, n\}Jn={1,2,3,…,n} হলে n(Jn)=?n(J_n) = ?n(Jn)=?a111bnnncn2n^2n2d