1. How do you know if the value found in a problem is a maximum value or a minimum value?
If the original function is a parabola examine the sign of x2. If it is negative, there will be a maximum involved.
Another way is to examine values either side of the stationary point.
2. If the velocity is negative, what does this mean?
A negative velocity means that the object is moving backward from its starting point.
3. What does a negative acceleration indicate?
A negative acceleration indicates that an object is slowing down.
4. If the acceleration of an object is zero does this mean that it is not moving?
No, not necessarily, The object's speed would be constant. i.e. The object would not be speeding up or slowing down.