Aresearcher working with college-age football players is conducting a longitudinal study to examine an athlete's decline in on-the-field performance as the athlete ages. what type of development would the researcher most likely be studying?

I believe the answer is: physical development

In longitudinal study same subjects over a certain period of time.  From the study above, we can see that on-field-performance is the dependent variables. Since there is no way for the researchers to conduct and proof the psychological development, physical development ia the most suitable choice.

b) trade is easy because of the direct line between their major ports. bilateral trade reached 89,6 thousand million.

during the nancy. probs