1) The national animal of Canada is the beaver.

2) The role of the judiciary is to interpret laws, resolve disputes, and ensure justice in accordance with legal principles and the constitution. It serves as a check on the executive and legislative branches of government.

3) The world's oldest living plant is believed to be a clonal shrub called "Old Tjikko" in Sweden, estimated to be over 9,500 years old.

4) The word "oxygen" contains two vowels: O and E.