Instances of overregularization occur in less than _____ percent of the instances when children use irregular words

Empirical investigation is

a. a study that makes logical sense. b. the collection of objective information by means of careful measurements. c. based on random coding of data. d. biased by random procedures. e. always found to be accurate.

___________ disorders are medical problems caused by the interaction of psychological, emotional, and physical difficulties

a. Psychosocial c. Psychosexual b. Psychosomatic d. Psychosybiotic