A lamina occupies the region inside the circle x2 + y2 = 10y but outside the circle x2 + y2 = 25. Find the center of mass if the density at any point is inversely proportional to its distance from the origin.

If the spring constant k of a pogo stick is 3500 n m and the weight of the person on the pogo stick is 700 n, how much is the spring in the botom of the pogo stick compressed?

What sort of waves exhibit the doppler effect?

An owl dives toward the ground with a constant velocity of 4.40 m/s at 53.0° below the horizontal. the sun is directly overhead and casts a shadow of the owl directly below it. what is the speed (in m/s) of its shadow on level ground?