Why are these answers correct?

7. The figure shows a box on a horizontal surface. Which of the following best shows velocity vectors if the box is moving along the surface to the left with increasing speed? Velocity Acceleration A. Negative Positive V B. Negative Negative C. Positive Positive D. Positive Negative E. Negative 0IL. MOTION GRAPHS A. x-t graph Question Proof/Work/Explanation A small sphere is launched straight upward. The vertical position as a function of time is shown in the graph. 50- Vertical Position (m) -50 -100 B Time (s) 1. Which of the following best describes the sphere's velocity during the time period shown? The velocity is always negative and A. decreasing. B. The velocity is always negative and constant. The velocity is initially positive, V C. decreases to zero, and then becomes negative D. The velocity is always positive and decreasing. E. The velocity is always positive and increasing 2. Which of the following relationships is best represented by the graph shown? The position is directly related to A time. B. The position is directly related to time squared. C. The position is directly related to 1/time. D. The position is directly related to 1/time squared.3. The graph shows the position x as a function of time t of an object in linear motion. Which of the following graphs best represents the velocity v of the object as a function of t? O VA B. C O D.4. The position x as a function of time t for an object moving in a straight line is shown in the graph above. Which of the following best describes the object's speed and direction of motion during the time interval shown? Speed Direction of motion A. Decreasing positive B. increasing positive V C. constant positive D. Decreasing negative E. increasing negativeB. v-t graph Question Proof/Work/Explanation 1. An object is moving along a straight line. The object's velocity as a function of time is shown in the graph above. Velocity (m's) Time (9) The object has a speed of 2 m/s at which of the following times? A. 1s only B. 6 sonly C. 9sonly D. 4 s and 10 s only V E. 1s, 6 s, and 9 s 2. During which of the labeled segments on the graph is the object moving but not accelerating? A. A V B. B C. C D. D E