You may remember that fresh water is the only type of water humans and animals can drink. For this reason, it is essential to life. What percentage of all water on Earth is fresh?
Question 2 options:

75%

90%

25%

3%

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.