Answer
The variable k in the equation $y=k+\sin x$ determines the vertical shift of the graph.
$y = 0 + \sin x$ -> no vertical shift
$y = 1 + \sin x$ -> 1 unit vertical shift above the original position
$y = -1 + \sin x$ -> 1 unit vertical shift below the original position
Work Step by Step
See below graph for reference:
