During an investigation into the nuclear instability of a sample of bismuth-212 (${}^{212}Bi$), a physicist subjects the sample to extreme physical conditions, including a temperature of 1.5 K and a pressure of $10GPa$.

The physicist records two key experimental observations:

1. The decay rate of the sample remains completely unchanged despite these extreme external conditions.
2. While the overall decay rate of the sample can be measured, it is impossible to predict which individual ${}^{212}Bi$ nucleus will decay next.

Which row in the table correctly identifies the physical terms used to describe Observation 1 and Observation 2?