Using Perl Identifiers (Answer)

@abc = ("Hi", "there", "how", "are", "you?"); print "@abc\n";

Sets the contents of @abc and prints it, giving: Hi there how are you?.
($abc) = ("Hi", "there", "how", "are", "you?"); print "$abc\n";

When assigning a longer list to a shorter, we loose the extra items at the right. Therefore $abc is assigned "Hi", and the program prints Hi.
@abc = ("Hi", "there", "how", "are", "you?"); print "$abc[2]\n";

Prints how.
@abc = ("Hi", "there", "how", "are", "you?"); print "$abc\n";

Since $abc is a different variable, unrelated to @abc, it is uninitialized and equal to the empty string. Only the newline is printed.

Using Perl Identifiers (Answer)
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