Final answer:
The provided information does not specifically mention the activities of psychologists, but it does provide information on the employment options of individuals with a PhD in psychology.
Step-by-step explanation:
The question asks about the percentage of US psychologists engaged in each activity. Unfortunately, the provided information does not specifically mention the activities of psychologists.
However, it does provide information about the employment options for individuals with a PhD in psychology, such as business, education, engineering, and professional occupations. It is important to note that this information may not reflect the percentage of psychologists engaged in each activity, but rather the occupations of individuals with a psychology degree. Further research may be needed to obtain more specific data on the activities of psychologists.