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# NaiveTicket
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-The second Objects lab,from the BlueJ book's second chapter.
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+The second Objects lab, from the BlueJ book's second chapter.
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-Look for the [Chapter 2 file](./doc/BlueJ-objects-first-ch2.pdf) you need in the [doc](./doc) folder. There is 35 pages of reading and exercises in the chapter.
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+Look for the [Chapter 2 file](./doc/BlueJ-objects-first-ch2.pdf) you need in the [doc](./doc) folder.
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+There is 35 pages of reading and exercises in the chapter.
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Work through all these exercises. You edit this file with your answers for these exercises.
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-* Exercise 2.1 Create a TicketMachine object on the object bench and take a look
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-at its methods. You should see the following: getBalance, getPrice, insertMoney,
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-and printTicket. Try out the getPrice method. You should see a return value containing
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-the price of the tickets that was set when this object was created. Use the
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-insertMoney method to simulate inserting an amount of money into the machine and
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-then use getBalance to check that the machine has a record of the amount inserted.
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-You can insert several separate amounts of money into the machine, just like you might
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-insert multiple coins or notes into a real machine. Try inserting the exact amount
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-required for a ticket. As this is a simple machine, a ticket will not be issued automatically,
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-so once you have inserted enough money, call the printTicket method. A
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-facsimile ticket should be printed in the BlueJ terminal window.
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-* Exercise 2.2 What value is returned if you check the machine’s balance after it
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-has printed a ticket?
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-* Exercise 2.3 Experiment with inserting different amounts of money before printing
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-tickets. Do you notice anything strange about the machine’s behavior? What happens
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-if you insert too much money into the machine – do you receive any refund? What
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-happens if you do not insert enough and then try to print a ticket?
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-* Exercise 2.4 Try to obtain a good understanding of a ticket machine’s behavior by
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-interacting with it on the object bench before we start looking at how the
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-TicketMachine class is implemented in the next section.
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-* Exercise 2.5 Create another ticket machine for tickets of a different price. Buy a
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-ticket from that machine. Does the printed ticket look different?
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-
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-* Exercise 2.6 Write out what you think the outer wrappers of the Student and
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-LabClass classes might look like – do not worry about the inner part.
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-* Exercise 2.7 Does it matter whether we write
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-`public class TicketMachine`
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-or
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-`class public TicketMachine`
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-in the outer wrapper of a class? Edit the source of the TicketMachine class to
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-make the change and then close the editor window. Do you notice a change in the
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-class diagram?
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-What error message do you get when you now press the Compile button? Do you think
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-this message clearly explains what is wrong?
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-* Exercise 2.8 Check whether or not it is possible to leave out the word public
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-from the outer wrapper of the TicketMachine class.
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-
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-* Exercise 2.9 From your earlier experimentation with the ticket machine objects
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-within BlueJ you can probably remember the names of some of the methods –
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-printTicket, for instance. Look at the class definition in Code 2.1 and use this
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-knowledge, along with the additional information about ordering we have given you,
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-to try to make a list of the names of the fields, constructors, and methods in the
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-TicketMachine class. Hint: There is only one constructor in the class.
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-Exercise 2.10 Do you notice any features of the constructor that make it significantly
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-different from the other methods of the class?
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-
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-* Exercise 2.11 What do you think is the type of each of the following fields?
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+### Exercise 2.1
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+* Create a TicketMachine object on the object bench.
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+* Upon viewing its methods, `getBalance`, `getPrice`, `insertMoney`, `printTicket`.
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+* Use `getPrice` method to view the value of the price of the tickets that was set when this object was created.
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+* Use `insertMoney` method to simulate inserting an amount of money into the machine.
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+* Use `getBalance` to check that the machine has a record of the amount inserted.
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+ * You can insert several separate amounts of money into the machine, just like you might insert multiple coins or notes into a real machine. Try inserting the exact amount required for a ticket. As this is a simple machine, a ticket will not be issued automatically, so once you have inserted enough money, call the `printTicket` method. A facsimile ticket should be printed in the BlueJ terminal window.
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+
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+### Exercise 2.2
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+* What value is returned if you check the machine’s balance after it has printed a ticket?
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+
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+### Exercise 2.3
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+* Experiment with inserting different amounts of money before printing tickets.
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+ * Do you notice anything strange about the machine’s behavior?
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+ * What happens if you insert too much money into the machine – do you receive any refund?
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+ * What happens if you do not insert enough and then try to print a ticket?
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+
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+### Exercise 2.4
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+* Try to obtain a good understanding of a ticket machine’s behavior by interacting with it on the object bench before we start looking at how the `TicketMachine` class is implemented in the next section.
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+
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+### Exercise 2.5
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+* Create another ticket machine for tickets of a different price.
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+ * Buy a ticket from that machine.
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+ * Does the printed ticket look different?
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+
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+### Exercise 2.6
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+* Write out what you think the outer wrappers of the `Student` and `LabClass` classes might look like – do not worry about the inner part.
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+
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+### Exercise 2.7
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+Does it matter whether we write<br>
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+`public class TicketMachine`<br>
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+or<br>
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+`class public TicketMachine`<br>
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+in the outer wrapper of a class?
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+
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+* Edit the source of the `TicketMachine` class to make the change and then close the editor window.
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+ * Do you notice a change in the class diagram?
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+ * What error message do you get when you now press the compile button?
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+ * Do you think this message clearly explains what is wrong?
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+
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+### Exercise 2.8
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+* Check whether or not it is possible to leave out the word `public` from the outer wrapper of the `TicketMachine` class.
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+
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+### Exercise 2.9
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+* From your earlier experimentation with the ticket machine objects within BlueJ you can probably remember the names of some of the methods – `printTicket`, for instance.
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+ * Look at the class definition in Code 2.1 and use this knowledge, along with the additional information about ordering we have given you, to try to make a list of the names of the fields, constructors, and methods in the `TicketMachine` class.
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+ * Hint: There is only one constructor in the class.
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+
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+### Exercise 2.10
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+* Do you notice any features of the constructor that make it significantly different from the other methods of the class?
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+
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+### Exercise 2.11
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+* What do you think is the type of each of the following fields?
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```
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private int count;
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private Student representative;
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private Server host;
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```
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-* Exercise 2.12 What are the names of the following fields?
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+
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+### Exercise 2.12
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+* What are the names of the following fields?
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```
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private boolean alive;
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private Person tutor;
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private Game game;
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```
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-* Exercise 2.13 In the following field declaration from the TicketMachine class
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+### Exercise 2.13
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+In the following field declaration from the TicketMachine class<br>
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```
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private int price;
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-```
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-does it matter which order the three words appear in? Edit the TicketMachine class to
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-try different orderings. After each change, close the editor. Does the appearance of the
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-class diagram after each change give you a clue as to whether or not other orderings are
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-possible? Check by pressing the Compile button to see if there is an error message.
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-Make sure that you reinstate the original version after your experiments!
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-* Exercise 2.14 Is it always necessary to have a semicolon at the end of a field declaration?
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-Once again, experiment via the editor. The rule you will learn here is an
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-important one, so be sure to remember it.
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-* Exercise 2.15 Write in full the declaration for a field of type int whose name is
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-status.
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-* Exercise 2.16 To what class does the following constructor belong?
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+```<br>
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+does it matter which order the three words appear in?
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+* Edit the `TicketMachine` class to try different orderings. After each change, close the editor.
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+ * Does the appearance of the class diagram after each change give you a clue as to whether or not other orderings are
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+possible?
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+ * Check by pressing the compile button to see if there is an error message.
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+ * Make sure that you reinstantiate the original version after your experiments!
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+
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+### Exercise 2.14
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+* Is it always necessary to have a semicolon at the end of a field declaration?
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+* Once again, experiment via the editor.
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+* The rule you will learn here is an important one, so be sure to remember it.
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+
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+
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+### Exercise 2.15
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+* Write in full the declaration for a field of type `int` whose name is `status`.
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+
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+### Exercise 2.16
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+* To what class does the following constructor belong?
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```
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public Student(String name)
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```
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-* Exercise 2.17 How many parameters does the following constructor have and what are their types?
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+
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+### Exercise 2.17
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+* How many parameters does the following constructor have and what are their types?
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```
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public Book(String title, double price)
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```
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-* Exercise 2.18 Can you guess what types some of the Book class’s fields might be? Can you assume anything about the names of its fields?
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-Work all Exercises from 2.19 to 2.58 that are NOT marked *Challenge exercise*.
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+### Exercise 2.18
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+* Can you guess what types some of the `Book` class’s fields might be?
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+* Can you assume anything about the names of its fields?
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+
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+Work all Exercises from 2.19 to 2.58 that are **NOT** marked *Challenge exercise*.
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READ upto and INCLUDING section 2.15 of this chapter.
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