Given the geometric sequence where a1 = 3 and the common ratio is −1, what is the domain for n?

Need on this geometry question. explain how you did it.

Consider a cube that has sides of length l. now consider putting the largest sphere you can inside this cube without any point on the sphere lying outside of the cube. the volume ratio -volume of the sphere/ volume of the cube is 1. 5.2 × 10−1 2. 3.8 × 10−1 3. 1.9 4. 2.5 × 10−1 5. 3.8

Which of the functions graphed below has a removable discontinuity?