k (Optional) A string representing a valid locale. If you do not include a value for k, the function uses the ambient locale.
Note: This function only converts the Unicode characters U+41 through U+5A (of the ASCII character set) as well as the characters U+FF21 through U+FF3A (of the fullwidth character set)The following expressions are examples of using the Lower function:
This example converts the first occurrence of Address to all lowercase letters.