Provide one exception for each of the following general statements:
$(i)$ Metals are lustrous.
$(ii)$ Metals are solids at room temperature.
$(iii)$ Metals have high melting points.
$(iv)$ Non-metals are non-lustrous.
$(v)$ Non-metals are insulators or non-conductors of electricity.

(N/A) $(i)$ Lead is a metal that is not lustrous.
$(ii)$ Mercury is a metal that exists as a liquid at room temperature.
$(iii)$ Gallium and Caesium are metals that have very low melting points.
$(iv)$ Iodine is a non-metal that is lustrous.
$(v)$ Graphite (an allotrope of carbon) is a non-metal that is a good conductor of electricity.