Answer:
z = 0.33
Step-by-step explanation:
The test statistic z can be calculated as:

Where p' is the proportion of the sample and p is the value in H0. Additionally, σ is equal to:
![\sigma=\sqrt[]{(p(1-p))/(n)}](https://img.qammunity.org/2023/formulas/mathematics/college/9b5e5tu10a8dvqg2k2194gm1ec4sxr2xt6.png)
Where n is the size of the sample.
In this case, we have a sample of 136 subjects, so n = 136 and taking into account H0, p = 0.42. So, replacing the values, we get:
![\begin{gathered} \sigma=\sqrt[]{(0.42(1-0.42))/(136)} \\ \sigma=0.0423 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/1e4z6p6x3u98y1f2r2k0xt9ugiahu1yp7x.png)
Then, p' is the proportion of the sample, so it is equal to:
p' = 59/136 = 0.4338
Now, replacing p' = 0.4338, σ = 0.0423 and p = 0.42, we get that the test statistic is:

Therefore, the answer is:
z = 0.33