Multiple entities are allowed to enter an activity and be processed concurrently (at the same time at the same activity), independent of other entities.
1. Set the capacity of the activity to the maximum number of entities that can occupy the activity at any one time.
Example: Because a bank uses five tellers, the Bank_Teller activity is able to concurrently and independently handle up to five Customers at any given time.
TO DO: Create the activity with a Capacity of 5.