a. airplane became a more prototypical example of a vehicle shortly after the attacks, but it was judged less prototypical about 4 months later.
b. the number of connection weights for airplane decreased at the time of the attacks, but soon afterwards, the number of connection weights increased.
c. shortly after the attacks, airplane shifted from being a prototype to becoming an exemplar.
d. for experts, the meaning of airplane changed significantly; for novices, the meaning remained stable.