If it is no longer protected by copyright, there are no rights to obtain.
The song will be protected through 2050; recordings will be protected longer.
The carol itself is from the late 19th century and as such is no longer protected by copyright, but newer arrangements may be protected, and recordings are almost certainly protected as well.
Works no longer protected by copyright are said to be in the public domain.
Completed in 1915, "The End of the Trail" is no longer protected by copyright.
They aren't. Copyright protection is for a limited time, while trademarks can be protected in perpetuity as long as they are in use.
Yes; materials no longer protected by copyright can be altered or distributed freely.
For written works of art, copyright generally extends to 50 years after the author dies. In Shelley's case, his work is no longer copyright protected.
No. Since 1989, when copyright law was amended to bring it into alignment with the Berne Copyright Convention, it is no longer necessary for a copyright symbol to be displayed to establish or maintain protection. Copyright exists from the moment you create an original work, and that can be something as simple as a photo of your child.
John Donne's works are in the public domain as he passed away in 1631. This means that his works are no longer protected by copyright law and are freely available for public use and reproduction.
Written works are protected by copyright as soon as they are "fixed" in a tangible format, which is to say written down. Publishing is no longer required for protection.
The 1935 translation is no longer protected, but newer editions of the translation may have copyrightable content.