Who is one VP who took a very active role in government? What did he do?

On April 21, 1789, John Adams, the first vice president of the United States, began his duties as president of the Senate. Adams's role in the administration of George Washington was sharply constrained by the constitutional limits on the vice presidency and his own reluctance to encroach upon executive prerogative.

Explanation:

answer:

d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.