What is the appropriate drill size for tapping an M6x0.75 thread in a steel workpiece?
a) Same as for tapping an M6x1.0 thread in aluminum
b) Double the size needed for tapping an M6x1.0 thread in aluminum
c) Half the size needed for tapping an M6x1.0 thread in aluminum
d) One size smaller than for tapping an M6x1.0 thread in aluminum
