Question

_____ is the oldest possible age that members of a species can attain, whereas _____ is the average life span of individuals in a particular group.

Answer 1

I believe the answer is: . Life span; life expectancy

According to the data by united nations, the longest legally verified human life span is 122 years and 164 days.
As for life expectancy, the number would be differ regarding the nations where you live in. But Japan has the highest life expectancy, with well over 82 years old on average