100°, 134°
In the planar structure of the nitric acid molecule (\(\text{HNO}_3\)), the bond angle between \(\text{H-O-N}\) is approximately 102°, and the bond angle between \(\text{O-N-O}\) is around 130°. These angles are influenced by the electron repulsion around the nitrogen atom and the resonance structure of the molecule.
The half-life of a radioactive nucleus is 5 years. The fraction of the original sample that would decay in 15 years is: