What is it called when scientist in the same or similar field of study judge the quality of a fellow scientist's scientific claim?

How did slavery end in the united statesa. it ended with the emancipation proclamationb. it ended when the union won the civil warc. it ended with the fifteenth amendmentd. it ended with the 13th amendment

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.

What restrictive measure required voters to pay to vote