help me answer these questions:

Block X Block X of mass m is at rest at the top of a ramp, and the block's center of mass is at a height H; above the ground. Block X is then released from rest, and it slides down the ramp and collides with block Y of mass m, which is initially at rest and has its center of mass at a height / above the ground. At the moment before the collision, block X has a speed of v,. After the collision, block Y travels such that it lands at point P. Consider the block X-block Y system from the moment in time that block X is released from rest to the moment immediately after block X collides with block Y. Which of the following claims best describes the system? @ Because the total momentum of the system does not remain constant, the system is open. Because the total kinetic energy of the system does not remain constant, the system is open. @ Because the total momentum of the system remains constant, the system is closed. Because the total kinetic energy of the system remains constant, the system is closed. Block X of mass m is at rest at the top of a ramp, and the block's center of mass is at a height H; above the ground. Block X is then released from rest, and it slides down the ramp and collides with block Y of mass m, which is initially at rest and has its center of mass at a height h above the ground. At the moment before the collision, block X has a speed of v, After the collision, block Y travels such that it lands at point P. Consider the scenario in which block X is released from rest at a height H,, which is lower than H; but higher than h. Which of the following statements is true about the horizontal distance traveled by block Y as a projectile in the two scenarios? Assume the collision in both scenarios is elastic. The horizontal distance will be greater for block Y when block X is released from height H,. The horizontal distance will be greater for block Y when block X is released from height H;. The horizontal distance will be the same for block Y in both scenarios. The answer cannot be determined without knowing the exact height of H; and H,. Question 15 A student must analyze data collected from an experiment in which a block of mass 2 traveling with a speed v, collides with a block of mass M that is initially at rest. After the collision, the two blocks stick together. Which of the following applications of the equation for the conservation of momentum represent the initial and final momentum of the system for a completely inelastic collision between the blocks? Justify your selection. Select two answers. A 2Mwvy = 3va, because the blocks stick together after the collision. B 3Muvy = 3va, because the blocks stick together after the collision. 6 2Mwy = 2Mv s + Muvy, because the blocks stick together after the collision. D 2Mvy = Mvy + 3va, because the blocks do not stick together after the collision. Question 16 Object Y Object X Object X of mass m, travels to the right with a velocity v,. Object Y of mass 2m, moves to the left at 2v, as shown in the figure. The objects collide and then stick together. What is the change in kinetic energy of the two-object system from immediately before the collision to immediately after the collision? The kinetic energy increases by 6m 3. The kinetic energy increases by 3mu2. The kinetic energy decreases by 6m0vg. The kinetic energy decreases by 3m0vg