A skater spins in the counterclockwise direction, as seen from above. In what direction does the vector representing the angular momentum of the skater point?

A particle moves in a straight line past a point O, as shown below. At which point is the angular momentum maximum? If the distance between O and the line is 2 m, and the object has a mass of 2 kg and a velocity of 3 m/s, what is the maximum angular momentum of the particle with respect to O?

What is the angular momentum of a thin hoop of radius 2 m and mass 1 kg that is rotating at a velocity of 4 rad/s?

Two particles travel in parallel directions, as shown below. What is the total angular momentum of the system with respect to O?

Many times a spinning top will not only spin about its axis, but precess about a vertical axis, meaning its point of contact with the ground remains the same, but the top swings around the vertical axis at an angle. What is the direction of the change in angular momentum in this situation? Where does the torque come from which causes this change in angular momentum?