Except with cloning the other twin would be a different age as with current tech the clone is back to being a baby. You’d need rapid growth tech and mind transfer tech to at least make the clone have the same age, memories and personality, although that would most likely introduce other differences.
Yes and no
The Telco can say between what antennas you are. In urban areas with lots of antennas that’s still pretty accurate to almost say what building. Especially with 5G the number of antennas and accuracy go upto in some cases centimeter/inch accuracy so better than GPS. That last case would be in a mall with small antenna in each corridor.
In rural areas with data switched off that’s more like somewhere in that square mile, way worse than GPS.