diff --git a/README.md b/README.md
index 4f153b0..7124eca 100644
--- a/README.md
+++ b/README.md
@@ -16,13 +16,13 @@ Work through all these exercises. You edit this file with your answers for these
* 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.
### Exercise 2.2
-* What value is returned if you check the machine’s balance after it has printed a ticket?
+* What value is returned if you check the machine’s balance after it has printed a ticket? 0
### Exercise 2.3
* Experiment with inserting different amounts of money before printing tickets.
- * Do you notice anything strange about the machine’s behavior?
- * What happens if you insert too much money into the machine – do you receive any refund?
- * What happens if you do not insert enough and then try to print a ticket?
+ * Do you notice anything strange about the machine’s behavior? It always resets to 0.
+ * What happens if you insert too much money into the machine – do you receive any refund? No, you do not receive a refund.
+ * What happens if you do not insert enough and then try to print a ticket? I get the same message either way.
### Exercise 2.4
* 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.
@@ -30,25 +30,25 @@ Work through all these exercises. You edit this file with your answers for these
### Exercise 2.5
* Create another ticket machine for tickets of a different price.
* Buy a ticket from that machine.
- * Does the printed ticket look different?
+ * Does the printed ticket look different? It shows a different price and total.
### Exercise 2.6
-* Write out what you think the outer wrappers of the `Student` and `LabClass` classes might look like – do not worry about the inner part.
+* Write out what you think the outer wrappers of the `Student` and `LabClass` classes might look like – do not worry about the inner part. public class Student and public class LabClass respectively
### Exercise 2.7
Does it matter whether we write
`public class TicketMachine`
or
`class public TicketMachine`
-in the outer wrapper of a class?
+in the outer wrapper of a class? Yes. It would throw an error. The access level must be declared first.
* Edit the source of the `TicketMachine` class to make the change and then close the editor window.
- * Do you notice a change in the class diagram?
- * What error message do you get when you now press the compile button?
- * Do you think this message clearly explains what is wrong?
+ * Do you notice a change in the class diagram? Yes. The arrow now points back to the class it starts from.
+ * What error message do you get when you now press the compile button?
+ * Do you think this message clearly explains what is wrong? No.
### Exercise 2.8
-* Check whether or not it is possible to leave out the word `public` from the outer wrapper of the `TicketMachine` class.
+* Check whether or not it is possible to leave out the word `public` from the outer wrapper of the `TicketMachine` class. It compiled without an access level.
### Exercise 2.9
* 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.
@@ -62,18 +62,18 @@ in the outer wrapper of a class?
* What do you think is the type of each of the following fields?
```java
-private int count;
-private Student representative;
-private Server host;
+private int count; Primitive integer
+private Student representative; Student
+private Server host; Server
```
### Exercise 2.12
* What are the names of the following fields?
```java
-private boolean alive;
-private Person tutor;
-private Game game;
+private boolean alive; alive
+private Person tutor; tutor
+private Game game; game
```
### Exercise 2.13
@@ -82,36 +82,36 @@ In the following field declaration from the TicketMachine class
```java
private int price;
```
-does it matter which order the three words appear in?
+does it matter which order the three words appear in? Yes.
* Edit the `TicketMachine` class to try different orderings. After each change, close the editor.
* Does the appearance of the class diagram after each change give you a clue as to whether or not other orderings are
-possible?
- * Check by pressing the compile button to see if there is an error message.
+possible? Yes. In the order of the class turned grey.
+ * Check by pressing the compile button to see if there is an error message. There is an error message stating "cannot find symbol variable price"
* Make sure that you reinstantiate the original version after your experiments!
### Exercise 2.14
-* Is it always necessary to have a semicolon at the end of a field declaration?
+* Is it always necessary to have a semicolon at the end of a field declaration? Yes.
* Once again, experiment via the editor.
* The rule you will learn here is an important one, so be sure to remember it.
### Exercise 2.15
-* Write in full the declaration for a field of type `int` whose name is `status`.
+* Write in full the declaration for a field of type `int` whose name is `status`. int status;
### Exercise 2.16
-* To what class does the following constructor belong?
+* To what class does the following constructor belong? Student
```
public Student(String name)
```
### Exercise 2.17
-* How many parameters does the following constructor have and what are their types?
+* How many parameters does the following constructor have and what are their types? Two. Both strings.
```
public Book(String title, double price)
```
### 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?
+* Can you guess what types some of the `Book` class’s fields might be? Strings, dates, numbers.
+* Can you assume anything about the names of its fields? Author, title, date published, ISDN
READ upto and INCLUDING section 2.15 of this chapter.
diff --git a/bluej.pkg b/bluej.pkg
index bf25784..b453f81 100644
--- a/bluej.pkg
+++ b/bluej.pkg
@@ -1,20 +1,23 @@
#BlueJ package file
-editor.fx.0.height=722
+dependency1.from=TicketMachineTest
+dependency1.to=TicketMachine
+dependency1.type=UsesDependency
+editor.fx.0.height=683
editor.fx.0.width=800
-editor.fx.0.x=709
-editor.fx.0.y=113
+editor.fx.0.x=262
+editor.fx.0.y=23
objectbench.height=101
-objectbench.width=461
+objectbench.width=776
package.divider.horizontal=0.6
package.divider.vertical=0.8007380073800738
package.editor.height=427
package.editor.width=674
-package.editor.x=1067
-package.editor.y=119
+package.editor.x=204
+package.editor.y=76
package.frame.height=600
package.frame.width=800
-package.numDependencies=0
-package.numTargets=1
+package.numDependencies=1
+package.numTargets=2
package.showExtends=true
package.showUses=true
project.charset=UTF-8
@@ -24,9 +27,16 @@ readme.width=47
readme.x=10
readme.y=10
target1.height=50
-target1.name=TicketMachine
+target1.name=TicketMachineTest
target1.showInterface=false
-target1.type=ClassTarget
-target1.width=120
-target1.x=80
-target1.y=50
+target1.type=UnitTestTargetJunit4
+target1.width=140
+target1.x=10
+target1.y=110
+target2.height=50
+target2.name=TicketMachine
+target2.showInterface=false
+target2.type=ClassTarget
+target2.width=120
+target2.x=160
+target2.y=40
diff --git a/package.bluej b/package.bluej
index bf25784..b453f81 100644
--- a/package.bluej
+++ b/package.bluej
@@ -1,20 +1,23 @@
#BlueJ package file
-editor.fx.0.height=722
+dependency1.from=TicketMachineTest
+dependency1.to=TicketMachine
+dependency1.type=UsesDependency
+editor.fx.0.height=683
editor.fx.0.width=800
-editor.fx.0.x=709
-editor.fx.0.y=113
+editor.fx.0.x=262
+editor.fx.0.y=23
objectbench.height=101
-objectbench.width=461
+objectbench.width=776
package.divider.horizontal=0.6
package.divider.vertical=0.8007380073800738
package.editor.height=427
package.editor.width=674
-package.editor.x=1067
-package.editor.y=119
+package.editor.x=204
+package.editor.y=76
package.frame.height=600
package.frame.width=800
-package.numDependencies=0
-package.numTargets=1
+package.numDependencies=1
+package.numTargets=2
package.showExtends=true
package.showUses=true
project.charset=UTF-8
@@ -24,9 +27,16 @@ readme.width=47
readme.x=10
readme.y=10
target1.height=50
-target1.name=TicketMachine
+target1.name=TicketMachineTest
target1.showInterface=false
-target1.type=ClassTarget
-target1.width=120
-target1.x=80
-target1.y=50
+target1.type=UnitTestTargetJunit4
+target1.width=140
+target1.x=10
+target1.y=110
+target2.height=50
+target2.name=TicketMachine
+target2.showInterface=false
+target2.type=ClassTarget
+target2.width=120
+target2.x=160
+target2.y=40