a. Create a class named RectangularPrism that has instance variables length, width, and height. b. Create a constructor that sets those variables. Also, create get and set methods for each variable. c. Create a toString() method. d. Create an equals() method. e. Create a hashCode() method. f. Create a HashSet of RectangularPrism and insert a few elements including duplicates. Verify that the HashSet removes all the duplicates.