Consider the following program code:

@array = ("one", "two");

push(@array, "three");

shift(@array);

unshift(@array, "four");

pop(@array);

print($array[0]);

What is the output of this code?

Regular expressions are best used for which task?

Consider the following program code:

@array = ("Y", "W", "X");

@array = sort(@array);

unshift(@array, "Z");

print(@array[0]);

What is the output of this code?