Which of the following species is not stable?

Identify the correct statements among the following:
$a$) $C_{60}$ molecule has $12$ five-membered rings and $20$ six-membered rings.
$b$) $H_2CO_3 / HCO_3^-$ buffer system helps to maintain $pH$ of blood between $7.26$ and $7.42$.
$c$) Graphite is used as a dry lubricant in machines running at high temperatures.

Identify the correct statements from the following:
$(a)$ $CO_{2(s)}$ (dry ice) is used as a refrigerant for ice-cream and frozen food.
$(b)$ The structure of $C_{60}$ contains $20$ six-membered rings and $12$ five-membered rings.
$(c)$ $ZSM-5$,a type of zeolite,is used to convert alcohols into gasoline.
$(d)$ $CO$ is a colorless and odorless gas.

In $C_{60}$,all carbon atoms are .......

Identify the incorrect statements from the following:
$I.$ Tin in $+2$ state acts as a reducing agent,while lead in $+4$ state acts as a strong oxidising agent.
$II.$ Silicon exists as both $[SiF_6]^{2-}$ and $[SiCl_6]^{2-}$ forms.
$III.$ The hybridisation of carbon in fullerene is $sp^3$.
$IV.$ Among $Ge$,$Sn$,and $Pb$,the lowest melting point is for $Sn$.

The number of six-membered and five-membered rings in Buckminster fullerene respectively is