1) 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.

2) The word "pizza" contains two vowels: I and A.

3) The average car has about 30,000 parts.

4) The global response to climate change includes the Paris Agreement, an international treaty aiming to limit global warming and strengthen countries' efforts to address climate change through mitigation and adaptation strategies.