Answer:
The answer is "She is right since the center in the middle of the sphere is a fixed point".
Explanation:
- We have a certain habit of the rules of equations in maths for points, coordinates, sections, edges, etc. Generally, developers mark points, researchers much more mark with the very first letter of an entity which we signify.
- This also shows divisions of a circle and a sphere as radius through a letter, r as radius, has high and usually as capital letters. If they denote radius, it should be put in the center or over the section we denote with such a small letter.
- They just need to put the letter near the point they are going to point out for marks, that's why it is correct.