The slope of the line on a position-time graph reveals information about an object's velocity. What conclusion can you draw regarding the motion of an object,if the graph is a
$(i)$ Horizontal line.
$(ii)$ Straight diagonal line.
$(iii)$ Curved line.

(N/A) $(i)$ $A$ horizontal line indicates that the position of the object does not change with time,meaning the object is at rest.
$(ii)$ $A$ straight diagonal line indicates a constant slope,which means the object is moving with uniform velocity (constant speed).
$(iii)$ $A$ curved line indicates a changing slope,which means the object is moving with non-uniform velocity (variable speed/acceleration).