1) Improved meteorological forecasting and early warning systems have significantly contributed to better preparedness and mitigation efforts for cyclones, reducing the loss of life and property.

2) International relations encompass the study of relationships between nations, including diplomacy, treaties, and foreign policy. It examines the interactions and dynamics among different countries in the global arena.

3) The Earth's core is hotter than the surface of the Sun.

4) The concept of sovereignty refers to the supreme authority and power of a state to govern itself, make decisions, and control its own territory without interference from external forces.