Final answer:
The object has a negative acceleration of 4 m/s² because its velocity decreases by 40 m/s over 10 seconds, indicating it is slowing down in the direction it was initially moving.
Step-by-step explanation:
An object moving east with a decrease in velocity from 65 m/s to 25 m/s over 10 seconds experiences a change in velocity of 40 m/s (65 m/s - 25 m/s). To calculate the acceleration, we divide this change in velocity by the time it takes for the change to occur, which is 10 seconds. This gives us an acceleration of -4 m/s² (40 m/s / 10 s), where the negative sign indicates the acceleration is in the opposite direction of the initial velocity, which is west.
The correct answer is A) Negative acceleration of 4 m/s², confirms that the object is slowing down in the direction it was moving (east).