Need help understanding this statistics problem - hypothesis testing!

 Hey everyone,

I’m struggling with a statistics problem involving hypothesis testing. It’s about comparing the means of two independent samples, but I’m not sure which test to use (t-test vs. z-test) and how to correctly set up the null and alternative hypotheses.  Sprunki Retake

I’ve attached the problem below (or a link to a screenshot, if allowed). If anyone could walk me through the steps, especially on choosing the right test and formulating the hypotheses, I’d really appreciate it!