13. Under a federal system of government, powers are equally distributed between
a dictator and an oligarchy
a central government and a legislative branch of government
a direct and an indirect democracy
a central government and local governments

What produces a record of seismic waves? richter scale seismogram barometer seismograph

The earth is constantly spinning on its axis, like you might spin a basketball on your finger. it is this spinning of the earth that causes

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.