Which of the following extends infinitely in two dimensions?

Which of the following is a flat surface with no thickness?

Which of the following has length but no width, and no height?

Which of the following extends infinitely in one dimension?

Which of the following represents only a position?

Which of the following has no length, no width, and no height?

Which of the following does not extend infinitely?

Which of the following is denoted by capital letters and the symbol ↔?

Which of the following is a set of points?

Which of the following has length and width, but no height?