Plot the pressure coefficient $C_p$ as a function of the distance along the airfoil for each angle of attack $($you should have $5$ figures in total$)-$ please use the attached excel file which does most of the work for you; you only have to change the values in the highlighted sections. Does it look similar to a nominal $C_p$ figure shown below?

From Introduction to Flight by Anderson

Note: $C_p$ distribution is traditionally plotted with the positive $C_p$ downward.

$C_p=\frac{p-p_{}}{\frac{1}{2}{}_{\text{a}\text{i}\text{r}}{V}_{}^2}$

$p_{}$ is the freestream pressure $($pressure in the flow far from the airfoil but still moving at the wind tunnel airspeed$)$ and for a wind tunnel is given by $($using Bernoulli's equation$)$:

$p_{}=p_{\text{a}\text{m}\text{b}\text{i}\text{e}\text{n}\text{t}}-\frac{1}{2}{}_{\text{a}\text{i}\text{r}}{V}_{}^2$

Note: Negative $C_p$ indicates suction and most of the lift $($the area between the two curves$)$ comes from the suction. $C_p=1$ indicates the stagnation point, i$.$e$.,$ point where the pressure is equal to the freestream pressure corresponding to the zero local velocity.