Under certain cutting conditions, doubling the cutting speed reduces the tool life to th 1 16 ? ? ?.

Under certain cutting conditions, doubling the cutting speed reduces the tool life to th 1 16 ? ? ? ? ? ? of the original. Taylor?s tool life index(n) for this tool-workpiece combination will be _______. The value of ? ? 2 x 0 4 1 cos x lim is 2x ? ? ?A 0? ? ? 1 B 2 ? ? 1 C 4 ?D undefined