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3.  An event is a change in an object’s state.                                            .....................
                     4.  Curly brackets {}, are not mandatory in a JavaScript function.                        .....................

                     5.  Strings are collections of 64-bit numbers.                                            .....................

                     6.  An event occurs when a user hits a button.                                            .....................
                     7.  The inbuilt function unshift( ) finds a match within a string.                        .....................
                     8.  JavaScript is an interpreted programming language.

                     9.  The slice() method modifies the original array.

                    10.  The inbuilt function substring( ) returns the position of the first match.            .....................


                   Ans.  1.  True   2.  False   3. True   4. False   5. False   6. True   7. False   8. True    9. False   10. False


                                                                Section B
                                                        (Subjective Type Questions)

                 A.  Short answer type questions.
                     1.  Which of the following are valid JavaScript function names?
                       Add() , function() , average1(), my.name(), NaN(), 2ndobject(), obj_hello(), wellness().

                  Ans.  Add(), average1(), obj_hello(), wellness()
                     2.  Differentiate between replace() and replaceAll() functions with examples.
                  Ans.   replace(): It replaces the first occurrence of a substring with another string.
                         For example:
                         var str = "Hello World";

                         var result = str.replace("World", "JavaScript");
                         document.write(result);
                         Output:

                         Hello JavaScript
                         replaceAll(): It replaces all occurrences  of a specified substring with another string.
                         For example:
                         var str = "apple apple apple";

                         var result = str.replaceAll("apple", "banana");
                         document.write(result);
                         Output:
                         banana banana banana
                     3.  Explain substring( ) and reverse( ) functions with examples.

                  Ans.    substring( ): It extracts the substring using the starting and ending positions as parameters. If the ending
                         position is left blank, the string will be extracted from beginning to end.
                         For example: str1 = "Pineapple is very tasty!";
                         document.write(str1.substring(7,20))
                         Output: le is very ta
                         reverse( ): The order of the elements in an array is reversed via the reverse() method. The original array is
                         overwritten.

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