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What are the challenges with parallel arrays as opposed to an array of objects?

When an array of objects is declared but not initialized, the array values are set to null

Suppose you had two data definition classes, Disease and ViralDisease. ViralDisease extends Disease. Assume in your implementation class, you had created an array of Disease objects. When looping through the array of Disease objects, how would you check to see if the current object was a ViralDisease?

Which key word indicates that a class inherits from another class?

What is an abstract method?

Assume you have three data definition classes, Person, Student and Faculty. The Student and Faculty classes extend Person.  Given the code snippet below, in Java, complete the method determinePersonTypeCount to print out how many Student and Faculty objects exist within the Person array. You may assume that each object within the Person[] is either referencing a Student or Faculty object. public static void determinePersonTypeCount(Person[] people){   // Place your code here }

Aggregation and Composition are not examples of an association.

All methods in an abstract class must be abstract.

A subclass may call an overridden superclass method by __________.

Given the data definition classes below, add line(s) to the implementation class HouseImplementation to demonstrate polymorphism.   1 public class House {2    public void setAddress(){}3    public double calculateCost(){}4 }   1 public class NewConstruction extends House {2    public double calculateCost(){}3    public void setMaterialList(String[] list){}4 }   1 public class HouseImplementation {2    public static void main (String[] args){3       // Lines will go here 4    }5 }