E$1.$ Draw sequence diagrams representing the following interactions:

$($a$)$ A client searches for a book in a library. He or she then asks to borrow the book. If

a copy of this book is available, a loan object is created.

$($b$)$ A client wishes to open a new account at a bank branch. To do so$,$ his instance of class

Client must first be retrieved from the central bank server. For a new client, an

instance of Client must be created. An instance of BankAccount is then created

using the Client object. A deposit must then immediately follow, to complete the

account creation process.

E$2.$ Draw communication diagrams for the interactions described in Exercise E$1.$

E$3.$ Given the state diagram in Figure $1,$ in what state would the system be in after the following

sequences of events? Assume that minimum is set to $3$ and maximum is set to $8.$

$($a$)$ openRegistration, requestToRegister $($repeated twice$),$ cancel.

$($b$)$ openRegistration, requestToRegister $($repeated $5$ times in total$),$

closeRegistration.

Figure $1$: State diagram of a CourseSection class