Why is it important to determine the credibility of a source?

After the civil war which president was called a "carpetbagger"? a. lincolnb. johnsonb. grant

What do most climatologists see as a major cause of rising global temperatures? a. earth's closer proximity to the sun due to its gravitational pull b. greenhouse gases produced by burning fossil fuels c. rising ocean levels caused by melting polar ice sheets d. water pollution cause by industrial waste

What did hiram rhodes revels argue for in the senate