To answer this question, you need to understand the different types of item renderers available in Flex and their use cases.

Option A) DropIn ItemRenderer - This option is incorrect because a DropIn item renderer is designed to be used in a single column of a DataGrid. It cannot be used in multiple columns.

Option B) Inline ItemRenderer - This option is incorrect because an Inline item renderer is also designed to be used in a single column of a DataGrid. It cannot be used in multiple columns.

Option C) Custom Component ItemRenderer - This option is correct because a Custom Component item renderer can be created and used in multiple columns of a DataGrid. By creating a custom component item renderer, you can define the desired behavior and appearance and reuse it across multiple columns.

Option D) No way to do that in Flex - This option is incorrect because Flex provides the capability to create custom component item renderers that can be used in multiple columns of a DataGrid.

The correct answer is C) Custom Component ItemRenderer. This option is correct because it allows for the creation of a reusable item renderer that can be used in multiple columns of a DataGrid.

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To answer this question, let's go through the code step by step:

In the main method:

1. Set s = new HashSet(); - This creates a new HashSet object called s.
2. s.add(new Name("Donald", "Duck")); - This adds a new Name object with the first name "Donald" and last name "Duck" to the HashSet.
3. System.out.println(s.contains(new Name("Donald", "Duck"))); - This checks if a new Name object with the first name "Donald" and last name "Duck" is present in the HashSet using the contains method.

In the equals method:

1. if (!(o instanceof Name)) return false; - This checks if the passed object o is an instance of the Name class. If it is not, it returns false.
2. Name n = (Name)o; - This creates a new Name object n by casting the passed object o to the Name class.
3. return n.first.equals(first) && n.last.equals(last); - This checks if the first and last names of the passed Name object n are equal to the first and last names of the current Name object. If they are equal, it returns true, otherwise it returns false.

Based on the code, the output will be:

B. false

Explanation: The HashSet uses the equals method to check for object equality. In the equals method of the Name class, the comparison is based on the equality of the first and last names. Since the equals method is not overridden in the Name class, it uses the default implementation from the Object class, which checks for reference equality. Therefore, when calling s.contains(new Name("Donald", "Duck")), the HashSet will create a new Name object, and since it is a different object from the one added to the HashSet earlier, the contains method will return false.

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To answer this question, we need to understand the different types of joins in SQL.

A FULL OUTER JOIN returns all rows from both tables, including unmatched rows from both tables. It combines the results of a LEFT OUTER JOIN and a RIGHT OUTER JOIN.

Let's go through each option to understand why it is correct or incorrect:

Option A) You want all unmatched data from both tables - This option is correct because a FULL OUTER JOIN includes all unmatched data from both tables.

Option B) You want all matched data from both tables - This option is incorrect because a FULL OUTER JOIN includes both matched and unmatched data from both tables.

Option C) You want all matched and unmatched data from both tables - This option is incorrect because a FULL OUTER JOIN includes both matched and unmatched data, not just matched data.

Option D) You want all unmatched data from one table - This option is incorrect because a FULL OUTER JOIN includes unmatched data from both tables, not just one table.

The correct answer is Option A. A FULL OUTER JOIN is used when you want all unmatched data from both tables.

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• Wrong explanation