Indirectly, yes. If the graph is a straight line there is no acceleration, if the graph is not linear there is acceleration.
Speed-Versus-Time Graph and Distance-Versus-Time graph are the two types of graphs that can be used to analyze the motion of an accelerating object.
It is false
Yes it is.
The slope of the line of a distance versus time graph is the velocity of the object. If this is a constant, in other words the graph is a straight line, the object is not changing its velocity and so is not accelerating. If the object is accelerating, the velocity of the object will be changing, thus the graph will not be a straight line, but a curve - the amount of curvature (and direction) tells you how much the object is accelerating (and in what direction - velocity and acceleration are vector quantities with both magnitude and direction).
The slope at any point is the velocity, so you can construct a graph of that. The slope at any point on that graph is the acceleration. So you can construct a graph of that. The slope at any point on that is the rate of change of acceleration. And so on.
False. A negative slope on the velocity vs time graph indicates that the object is decelerating or slowing down, but it is still accelerating in the opposite direction.
The curved line on a time vs. distance graph represents that the object is accelerating.
speed
speed
False. A negative slope on a velocity vs. time graph indicates that the object is decelerating, not that it is not accelerating. Acceleration and deceleration are both forms of acceleration, but in opposite directions.
curve
it is a positive relationship