Question 715629
What would a math teacher think the right answer is?
I'll give you my guesses, but think of words mentioned in class. 
 
1.pencil _ I have some pencils shaped like hexagonal {{{highlight(prism)}}}s, and some other pencils shaped like {{{highlight(cylinder)}}}s, so that's what a pencil suggests to me, but
maybe the teacher thinks that a pencil suggests a line {{{highlight(segment)}}}.
2.beam of light - {{{highlight(parallel)}}} lines. The sun is so far away that the sun rays are parallel. If it is the beam of light from a spotlight, it would suggest a {{{highlight(cone)}}} to me; and the spot of light would suggest a {{{highlight(circle)}}}.
3.edge of a box _ a line {{{highlight(segment)}}}? a {{{highlight(line)}}}? a {{{highlight(dihedral)}}} angle?
4.clothesline _ a {{{highlight(line)}}} (although I you had studied Calculus, you would say a catenary)
5.cover of a book _ a {{{highlight(rectangle)}}} (I would not say a {{{highlight(plane)}}} , because planes go on forever in all directions and the cover of a book is small, but I don't know what the teacher thinks)
6.tip of a pencil _ The shape of a sharpened tip is a {{{highlight(cone)}}}, but maybe the teacher sees a {{{highlight(point)}}} in the pointy end of the pencil
7.top of a table _ a {{{highlight(plane)}}} (The top of the table does not go on forever, but it goes on for white a length)
8.speck of dust _ a {{{highlight(point)}}} 
9.edge of this page _ a line {{{highlight(segment)}}} because a whole line goes on forever in both directions
10.a sheet of paper _ a {{{highlight(rectangle)}}} , but maybe the teacher thinks of an endless {{{highlight(plane)}}}
11.sunlight _ I think of {{{highlight(parallel)}}} lines again.
12.table cloth _ I'm stumped. A curved {{{highlight(surface)}}} ?
13.intersection _ {{{highlight(angles)}}} ? {{{highlight(perpendicular)}}} lines?
14.tip of a ballpen _ a {{{highlight(sphere)}}} ? a {{{highlight(point)}}} ?
15.floor _ a {{{highlight(plane)}}}
 
Good luck. Smile. You may get puzzling assignments like this from time to time.