Express the following in the form of $\;a+bi : (-i) \; (2i)\;(-\large\frac{1}{8}i)^{3}$

Question

$(a)\;\large\frac{1}{256} i\qquad(b)\;\large\frac{3}{256}i \qquad(c)\;\large\frac{5}{256} i \qquad(d)\;\large\frac{5}{3} i$