$\begin{array}{1 1} \text{a. Greyish black in colour and bad conductor of electricity.} \\ \text{b.Slippery to touch and good conductor of electricity.} \\ \text{
c.Greyish black in colour and bad conductor of heat.} \\ \text{
d.Slippery to touch and good conductor of heat.}
\end{array} $
