1. Write a class Car.  A Car object should have two instance variables.  It should 
have mpg and gallons.  It should have two constructors. It should have two methods:  addGas and drive.
	
	A test class should contain this:
	
	Car myHybrid = new Car(49, 20);//Constructs a car that gets 49 mpg and has 20 gallons of gas
	myHybrid.addGas(20);//adds twenty more gallons of gas
	myHybrid.drive(100);//drives 100 miles
	System.out.println(myHybrid.getGas());//prints the remaining fuel
	
2.  Write a class Student.  A student should have one constructor with 3 parameters
Name, total quiz score, and total number of quizzes taken.  
Then, you shoiuld have the following methods:
	
		getName()
		addQuiz(int score)
		getTotalScore()
		getAverageScore()
	
	A Test program might look like this:
	
	public class StudentTest
	{	public static void main (String[]args)
		{	Student bob = new Student("Bob",0,0);
			bob.addQuiz(100);
			bob.addQuiz(75);
			bob.addQuiz(54);
			System.out.println(bob.getTotalScore());
			System.out.println(bob.getAverageScore());
			Student zero = new Student();
			System.out.println(zero.getAverageScore());
		}
	}
	
3.  Write a class SodaCan.  A test class could look like this:

	public class SodaCanTest
	{	public static void main(String[]args)
		{	SodaCan rite = new SodaCan(5,10); //5 is radius, 10 is height
			System.out.println(rite.getSurfaceArea());
			System.out.println(rite.getVolume());
		}
	}
	
4.  Write a class RoachPopulation.  The constructor should take the initial size of the roach
	population.  It should have methods doublePopulation and bugSpray.  The doublePopulation
	method should simply double the roach population.  The bugSpray method should decrease 
	the population by 10%.  There should also be a getPopulation method to determine how 
	many of the roaches are left.