posted by rfvv Wednesday, April 11, 2018 at 6:11pm

1. A dot is one-dimensional.
2. A surface is two-dimensional.
3. A cube is three-dimensional.

4. At is one-dimension.
5. At is the first dimension.

6. On is two-dimensions.
7. On is the second dimension.
8. On is two dimensions.

9. In is three-dimension.
10. In is three dimensions.
11. In is the third dimension.
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Which ones do we have to use?
MsPi_3.14159265 Wednesday, April 11, 2018 at 6:47pm
The ones that make sense are #1, #2, #3, #9 should read... It is in three dimensions
#10 should read ... It is in three dimensions
#11 should read... It is in the third dimension. That is, the z-coordinate is in the third dimension.
Hope this helps : )
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[Thank you for your help.]

1. A dot is one-dimensional.
2. A surface is two-dimensional.
3. A cube is three-dimensional.

12. At is one-dimensional.
13. At is in one dimension.
14. At is in the first dimension.
[Which one is correct? Do we have to use a cardinal number or ordinal number? By the way, is "at" one-dimensional? At can be compared to "a spot", can't it?]

15. On is two-dimensional.
16. On is in two dimension.
17. On is in two dimensions.
18. On is in the second dimension.
19. On is in the second dimensions.
[Which ones are correct? Do we have to use a cardinal number or ordinal number? Do we have to use singular nouns or plural nouns?]

#12.. should read "a point" such as a point on the graph.

#13 is just not a usual statement. It could be re-written as "The point on the graph is one-dimensional" If you need to re-write 13 it could say "the picture is drawn in two dimensions."
#14 doesn't work at all.
so again... 12 and 13 could be re-written to work, but 12 is best .
#15 A point is two-dimensional
#16 NOT CorrecT.
#17 A graph is in two dimensions
#18 The graph is two dimensional.... is the usual way to write this.
#19 The graph is two dimensional... is the usual way to write this.

To answer your first question, the correct sentence is #13: "At is in one dimension." In this case, we use a cardinal number (one) because we are referring to a single dimension.

Regarding whether "at" is one-dimensional, it can be thought of as being similar to "a spot" in some contexts. However, it is important to note that "at" is a preposition, whereas "a spot" refers to a physical object. In the given context, it seems like "at" is being used to describe a location in one dimension, hence the term "one-dimensional."

For your second question, the correct sentence is #17: "On is in two dimensions." Here, we use a cardinal number (two) because we are referring to two dimensions. Additionally, we use the plural form of the noun "dimensions" because we are talking about multiple dimensions.