QUESTION 3:
Think of three behaviors a checking account should have.
The following seem reasonable to me. You might have thought of others.
A real checking account would contain a great deal more state, but for this example, the above is enough. It is too early to think about what types of variables are going to be used for the above data. That will come later.
Next, think about what actions will be performed on a checking account. That is, what behavior will a checking account have?
Think of three behaviors a checking account should have.