The SUMSQ function syntax has the following arguments: Number1, number2, ... Number1 is required, subsequent numbers are optional. 1 to 255 arguments for which you want the sum of the squares. You can also use a single array or a reference to an array instead of arguments separated by commas.
THEY/THEIR (SINGULAR). Using the plural pronoun to refer to a single person of unspecified gender is an old and honorable pattern in English, not a newfangled bit of degeneracy or a politically correct plot to avoid sexism (though it often serves the latter purpose).
2. unusual or strange; odd; different: singular behavior. 3. being the only one of its kind; unique: a singular example. 4. separate; individual. 5. of or belonging to the grammatical category of number used to indicate that a word has one referent or denotes one person, place, thing, or instance, as child,it, or goes.