How will I know what billable activity a contractor has taken in a particular month?

You can view this information from the contractor's profile.

1. From the Team page, you can filter and get an overview of the billable contractors in a particular month.
   
   
   
   
2. Click on the contractor's name to go to their profile. 
3. On the contractor's profile, go to the Billable activity tab. This will list out the billable activities the contractor has taken and when they took the actions.