12. How long ago did early men exist?( years ago ) A 1.8 million years ago
B. 3.5 million years
( 33,000 years ago
D. 12,000 years ago

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.