The graph is parallel to the time axis, normally the horizontal axis.
It depends on what type of graph you use. If it is a line graph, and time is on the bottom and distance is on the left, it will result in a flat line from where ever it stopped.
object is at rest
A straight horizontal one does.
that would indicate that the object is at rest (static object) :D
If the line is parallel to the time axis, this means that the distance is not changing, so the object is not moving.
Energy is stored in form of chemical energy. It is stored in object at rest.
an object at rest will stay at rest
An object can be at rest with or without friction. An object floating in outer space can be at rest. An object that is glued to the floor can also be at rest.
The velocity-time graph is at y = 0.
Neither, it is an incomplete statement that could form part of a law, but of itself it is meaningless.
An object at rest has a velocity of zero.
the slope of distance time graph gives us velocity but when the body is at rest it will be zero