Who was the first african american to make serious run for president?

Alimitation on the president’s power to appoint ambassadors is that

Using mr smith and his id, identify two potential internal validity threats that might affect the a—b design. tell me how that threat might impact conclusions in the a—b design. note #1: you cannot use maturation (since i already did that one for note #2: there are some mr smith id threats that won’t have much impact in a single case design.

Ascientist who studies prehistoric and historic people by analyzing artifacts is a(n) a. historian b. botanist c. archaeologist d. anthropologist