Timing of ECs

Applying to College Common and Coalition Application
1

I participate in an EC more hours in a week during the summer than I do during the school year.
Where can I specify the exact numbers for the summer and the school year if I do not have any space in the description of EC section?

I thought maybe the Additional Info area, but I also heard some schools don’t even look at that section?

2

Just estimate the the average hours you do this EC over the course of the year.