Why did China decline after being the most advanced civilizations in the world ?

The civil rights act that passed in 1964

How did the construction of the erie canal improve transportation in the united states in the 1820s? a. the canal connected the great lakes to the mississippi river. b. the canal connected the great lakes to the ohio river. c. the canal connected the atlantic and pacific oceans. d. the canal connected the great lakes to the atlantic ocean.

Did the both the us and ussr have atomic weapons after 1949