help me answer these questions:

Question 7 Block X Block Y Vx i Figure 1. Before the collision Block X Block Y Vxy =X Figure 2. After the collision Block X slides along a horizontal surface with a speed vx toward block Y that is initially at rest, as shown in Figure 1. After block X collides with block Y, the two blocks remain stuck together and travel at a velocity of vxy, as shown in Figure 2. Frictional forces are considered to be negligible. Which of the following claims is correct regarding the momentum of the system containing only block X and the system that contains block X and block Y? @ The system containing block X is an open system, and the system of both blocks is an open system. The system containing block X is an open system, and the system of both blocks is a closed system. The system containing block X is a closed system, and the system of both blocks is an open system. The system containing block X is a closed system, and the system of both blocks is a closed system. o0 000000 4 kg object 0 2 kg object 7 6 5 . Z; ! 22 8 1 =0 -1 -2 -3po0ooooooo| 0 0.5 il Time (s) A student performs an experiment in which a 4 kg object travels across a horizontal surface with an initial speed velocity of 6 m/s and a 2 kg object travels across a horizontal surface with an initial speed velocity of 3 m/s. The objects travel toward each other and collide. Data collected from the experiment were used to create the velocity versus time graph shown that contains information about both objects before and after the collision. The positive direction is considered to be to the right. Which of the following statements are true regarding the data from the experiment? Both objects always travel in the positive direction during the experiment. Kinetic energy is conserved during the experiment. The position of the center of mass of the system remains constant during the experiment. The velocity of the center of mass of the two-object system remains constant during the experiment. Question 11 Mass of Trial Mass of Velocity of Object X Velocity of Object Y Time of Object X Number Object Y Before Collision ( Before Collision ( Average Force Exerted on Average Force Exerted on (kg) (kg) m/s) m/s) Object X by Object Y (N) Object Y by Object X (N) Collision (s) 2.1 1.1 2.2 -1.1 101 101 0.2 2 2.0 1.1 1.9 -1.0 105 105 0.2 3 1.9 1.0 2.0 -1.0 99 99 0.2 In an experiment, two objects, object X and object Y, travel toward each other and collide. Data are collected about each object before, during, and after the collision, as shown in the table. Which of the following pairs of data, when used together to create two graphs, could verify the conservation of momentum? Select two answers. A Average force exerted on object X by object Y and time of collision, because these measurements can be used to determine the change in momentum of object X. B Average force exerted on object Y by object X and time of collision, because these measurements can be used to determine the change in momentum of object Y. C Mass of object X and velocity of object X before collision, because these measurements can be used to determine the initial momentum of object X. D Mass of object Y and velocity of object Y before collision, because these measurements can be used to determine the initial momentum of object X.Question 12 Cartd Cait2 Velocity of Cart 1 Immediately Velocity of Cart 2 Immediately Velocity of Cart 1 Immediately Velocity of Cart 2 Immediately Mass Mass s i i i (ke) (kd) Before Collision (m/s) Before Collision (m/s) After Collision (m/s) After Collision (m/s) 1 2 4 0 1 1 A group of students conducts an experiment in which two carts collide with each other as they travel across a horizontal surface with negligible friction. Using motion detectors and a mass balance, the students collect data about the carts immediately before and immediately after the collision, as shown in the table. Which of the following claims is true regarding the momentum and the kinetic energy of the two-cart system for the experiment? Does the data indicate that a net external force acts on the system? @ The momentum is the same and the total kinetic energy of the system is the same immediately before the collision and immediately after the collision. This indicates that a net external force is not exerted on the system. The momentum is different and the total kinetic energy of the system is the same immediately before the collision and immediately after the collision. This indicates that a net external force is exerted on the system. The momentum is the same and the total kinetic energy of the system is different immediately before the collision and immediately after the collision. This indicates that a net external force is not exerted on the system. @ The momentum is different and the total kinetic energy of the system is different immediately before the collision and immediately after the collision. This indicates that a net external force is exerted on the system