Why did eastern europeans feel it was safe to rebel in 1989

The Soviet Union maintained its power through coercion and terror, in the late 1980s it lost the power and will to continue, and disintegrated.

From the Bolshevik Revolution in November 1917 onwards, the USSR maintained its rule through military power and ruthless security agencies.

worldwide, 780 million people do not have access to an improved water source. an estimated 2.5 billion people lack access to improved sanitation (more than 35% of the world's population)