1.
/**
  Gives the employee a raise in salary.  The raise is either a standard
  amount (2%) or adds an additional bonus raise (5% combined).
  @param isGoodEmployee tells if the employee should get the larger raise.
*/

2. 
public class SquareTester
{
   public static void main(String[] args)
   {
      Square sq = new Square(10);        //This line was added
      System.out.println(sq.getArea());
      System.out.println("Expected: 100");

      // grow and move back to original center
      sq.grow(3);      	       		//This line was added.
      sq.translate(-10, -10);		//This line was added.
      
      System.out.println(sq.getCenterX());
      System.out.println("Expected: 5");
      System.out.println(sq.getCenterY());
      System.out.println("Expected: 5");
      System.out.println(sq.getArea());
      System.out.println("Expected: 900");
   }
}

3. 
   public void bet(double wager, double winProbability)
   {
      if(winProbability < .5 || winProbability > 1) return;
      double random = Math.random(); 
      if (random < winProbability)
         funds = funds + wager; // The gambler won
      else
         funds = funds - wager; // The gambler lost
   }

4. 
public boolean hasWishesLeft()
   {
      return wishes < TOTAL_WISHES;
   }

5.
a)  None neeeded.
b)  String getLetterGrade() would first use getAverageScore(), and classify
the returned number into a letter grade by the given values (9.0 and
up is an A, etc.).
c)  No other changes are needed.

6.
I give the answer below, broken into separate method calls, with 
the values staggered by time even within one method call.  After that,
I give the simplified answer which is also acceptable.

       Robot  turnLeft moveBackward
x      0               1
y       0               0
dx       0       -1       
dy        -1    0        
newDx         -1   X      

Simplified version:
x      0        1
y      0        0
dx     0   -1       
dy     -1  0        
newDx      -1 X      

7. 
The paintComponent method is given below.  Note, it is nicer to put
the note on top of the staff, but I will also take the staff over the note.

public void paintComponent(Graphics g)
   {
      // Recover Graphics2D
      Graphics2D g2 = (Graphics2D) g;

      // Change to blue
      g2.setColor(Color.BLUE);

      // Make and draw lines
      Line2D.Double staff = new Line2D.Double(5, 20, 100, 20);
      g2.draw(staff);

      staff = new Line2D.Double(5, 30, 100, 30);
      g2.draw(staff);

      staff = new Line2D.Double(5, 40, 100, 40);
      g2.draw(staff);

      staff = new Line2D.Double(5, 50, 100, 50);
      g2.draw(staff);

      staff = new Line2D.Double(5, 60, 100, 60);
      g2.draw(staff);

      // Change back to black for the note.
      g2.setColor(Color.BLACK);

      // Construct and draw one note base
      Ellipse2D.Double base = new Ellipse2D.Double(10, 30, 10, 10);
      g2.fill(base);

      // Construct and draw the stem
      Line2D.Double stem = new Line2D.Double(19, 10, 19, 35);
      g2.draw(stem);
   }