Sodium, calcium, iron and gold are all metals. They all form metallic bonds, in the form of a shared electron cloud. They all have the electrical conductivity and metallic luster which comes with metallic bonds.
I see you have access to the internet. Google 'Kelvin to C', and input 251. You'll get -22.15.
It’s chlorine not iodine because as we go down the group non metallic character decreases
B) Series, because parallel is split into two making two loops for a current to flow.
