Taking this into consideration from the ml language: 6. there will be at most 50 unique identifiers appearing in any program lets just say a variable within a function is introduced, and then is set out of scope when exiting the function. The variable technically does not exist, does this still count towards the 50? as in there needs to be a max 50 in total, or just 50 concurrently function addwithb a b <- 10 return a * b #b no longer exists outside the function