You have to write formula like 

=IF(ISERROR([Column1]/[Column2]),"NA",[Column1]/[Column2])

Returns NA when the value is an error

Hope it helps

Regards,

Dhaval

Modifying a calculated column gives different errors
Can a Barbarian in Rage mode fight defensively or use Full Defense?

I didnt find any rule about it, I think there is something about using Combat Expertise, but nothing else.

In the session that the doubt come we end allowing the barbarian doing so, but seems odd.
