Xavier
The proper noun is Jessica, the name of a person. A proper noun always starts with a capital letter.
Nope. Common noun.
The boy names Thaddeus, Thornton, Tyler, Tate, Theodore, Todd, Trent, Tucker, Thomas, Taylor, Terry and Turner are proper nouns.
David's
NO!!! 'Janet' is a proper noun. It is a female forename. derived from the male 'John'. Being a proper noun it starts with a capital letter.
The word Tuesday is a proper noun because it's the name of a specific day.
X-ray
xanadu
Proper nouns.
Yes, T-shirt is correct.It is not necessary to capitalise the 't' in t-shirt. It is not a proper noun, but just a common noun. Capitalisation is not necessary even though the t-shirt was so named because it resembles a capital T.
Yes, "Stefan" is a proper noun because it is a specific name for a person, place, or thing. It always starts with a capital letter.