1) The Indian Ocean is the third-largest ocean and is characterized by its warm waters and diverse marine life.

2) The Eiffel Tower can be 15 cm taller during the summer due to thermal expansion.

3) Democracy is a system of government in which power is vested in the people, who exercise it through elected representatives. It allows for political participation, freedom of speech, and protection of individual rights and liberties.

4) The first commercially available digital camera, the Dycam Model 1, was introduced in 1990 and had a resolution of 376 x 240 pixels.