Answer
The plot of y versus x is in the shape of a negative sine function.
Work Step by Step
At $t = 2.5~s$, the displacement $y$ of the particle at $x = 0$ is $y = 4.0~cm$
It is given that the wave is moving in the positive x direction.
Thus, at $t = 0$, the peak of the wave was to the left of $x = 0$
Therefore, the plot of y versus x is in the shape of a negative sine function.
