A singular non is the opposite of a plural noun. A plural noun names more than one person, place, thing, or idea. A plural noun includes things like "children," "books," "libraries," or "liberties." A singular noun would be "child," "book," "library," and "liberty." Singular nouns only name one person, place, thing, or idea. Hope this helps.
I didn't actually understand the question but I will try to solve it.
Length of ribbon = 3 ft
Total number of small pieces = 8
So, length of each piece = 3/8 = 0.375 ft
The third choice, because it does not state where the idea came from