8. When two groups are involved in trade, what is generally MOST likely to occur?

A. Exchanges will be very formal, so they are taken seriously.

B. Most groups will not benefit from the trade.

C. Groups will try to use exchanges to better the group.

D. Competition and conflict will disrupt the trading process.

At a certain instant after jumping from the airplane a, a skydiver b is in the position shown and has reached a terminal (constant) speed vb = 52 m/s. the airplane has the same constant speed va = 52 m/s, and after a period of level flight is just beginning to follow the circular path shown of radius ρa = 2330 m. (a) determine the velocity and acceleration of the airplane relative to the skydiver. (b) determine the time rate of change of the speed vr of the airplane and the radius of curvature ρr of its path, both as observed by the nonrotating skydiver.