what does the second number in the numbering classification system for wrought aluminum alloys tell…

what does the second number in the numbering classification system for wrought aluminum alloys tell you?\nthe principal alloying element used or the alloy series\nan alloy modification\nan arbitrary number that identifies a specific alloy in a series
Answer
Brief Explanations:
In the numbering classification system for wrought aluminum alloys, the second number indicates an alloy modification. The first number typically relates to the principal alloying element or alloy series, and the last two - three numbers are often used to identify a specific alloy in a series.
Answer:
An alloy modification