College Physics (4th Edition)

$v_x = 1.0~m/s$
The slope of the $x$ versus $t$ graph is the velocity $v_x$. We can find the slope at $t = 2.0~s$: $slope = \frac{\Delta x}{\Delta t} = \frac{2.0~m}{2.0~s} = 1.0~m/s$ At $t = 2.0~s~$, $~v_x = 1.0~m/s$