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for proceeding would be to identify the scenario that belongs to the use case. You assign a unique identifier to the use case as well as the scenario, as follows:
Use Case 001: Open an Account
Scenario 01: The customer is a new customer with no previous accounts and has the minimum required balance.
Step 1: The teller provides the customer information to the system.
Step 2: The teller wants to check the customer's checking history with Telecheck.
Step 3: When the teller sees that the customer has a good checking history, the teller provides the opening deposit balance to the system.
Step 4: The teller prints out the new account information.
Notice that in elaborating on the steps involved in this use case, you uncovered some more significant nouns and verbs. They are as follows:
Nouns
Customer information
Customer
System
Checking history
Telecheck
Opening deposit balance
Account information

Verbs
Provide the customer information to the system
Check the customer's checking history
Provide the opening deposit balance to the system
Print out the new account information

Before creating the sequence diagram, you must again determine which nouns and verbs are significant.
Each of the nouns customer information and account information contains a word that provides a strong clue as to its importance in your proposed system: information. When users use words such as customer information or account information, these almost always imply properties (or attributes) of classes in your system. They certainly imply

 
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