Answer 3
Hi,
When a workflow assigns a task to a group that is identified by a single alias or address, the workflow creates only one task item, which is then shared by the entire group. Any member of the group can edit that single task form and click the Task Complete button. To assign individual tasks to multiple users (only possible with the Assign a Form to a Group or Assign a To-do Item action), enter each user individually in the Select Users dialog box.
So If you want assign individual tasks to 16 users, you should enter each user individually in the select users dialog box, you cannot add these users to a group.
Hope it helps.