Question

what can you say about motion of an object whose distance time graph is a straight line parallel to time axis

Answer 1

a graph of a uniform motion is a straight line.
and graph of non uniform motion is a curve line.
it means the speed is constant if the graph is a straight line (distance time graph).

Answer 2

Answer:-

When distance time graph is the straight line parallel to time axis then the body is at rest or stationery.