5. The Treaty of Guadalupe-Hidalgo ended the Mexican-American War in 1848. Because of this treaty, the United States grew in size by but Mexico lost almost of its territory.

a) one half / one third b) two fifths / one third c) one third / all d) one third / one half

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.