Question

what does a straight line going up on a position vs. time graph indicate? the object has stopped moving negative acceleration the object is returning to the origin positive constant velocity

Explanation:

In a position - vs - time graph, the slope represents velocity. A straight line going up has a positive constant slope. Since slope = $\frac{\Delta x}{\Delta t}$ (where $\Delta x$ is change in position and $\Delta t$ is change in time), a positive constant slope means the object is moving with a positive constant velocity.

Answer:

Positive constant velocity