Elements that do not require a closing tag are called empty elements.?

In the linked based implementation of a stack class, what does the default constructor initialize the private variable topPtr to?

a. OrigChainPtr b. newChainPtr c. nullPtr d. 0

What is the result of executing the following code?

``` 1 myResultSet = myStatement.executeQuery( 2 "SELECT age FROM people WHERE name = ’Bob’" ); 3 4 while ( myResultSet.next() ) 5 { 6 displayJTextArea.append( myResultSet.getInt( "age" ) + "\n"); 7 } ```