An activity on a PERT network has these time estimates: optimistic $=2,$ most likely $=3,$ and pessimistic $=8.$ What is its expected activity time and variance?

Select one:

a$.3\mathrm{.}67$;$1$

b$.3\mathrm{.}67$;$6$

C$.4\mathrm{.}33$;$6$

d$.4\mathrm{.}33$;$1$

e$.$ None of these