Which of the following has/have value equal to zero?

82712351643=82741−241−2R3→R3−R2 and R2→R2−R1=01/aa2bc1/bb2ac1/cc2ab=1abc1a3abc1b3abc1c3abcR1→aR1,R2→bR2,R3→cR3=abcabc1    a3    11    b3    11    c3    1  [taking abc common from C3]=0a+b2a+b3a+b2a+b3a+b4a+b4a+b5a+b6a+b=a+b2a+b3a+baaa2a2a2a =0R3→R3−R2,R2→R2−R1243673543172    =216774332    C2→C2−7C3    =116074032    C1→C1−C2    =2