Step 1 :The question is asking to determine the hypotheses for a statistical test. The null hypothesis (H0) is usually a statement of no effect or no difference. The alternative hypothesis (Ha) is what you might believe to be true or hope to prove true.
Step 2 :In this case, we are testing the hypothesis that the mean days surfed for all longboarders is larger than the mean days surfed for all shortboarders. So, the null hypothesis should be that the means are equal, and the alternative hypothesis should be that the mean for longboarders is greater than the mean for shortboarders.
Step 3 :The correct hypotheses for this test are: \n \[ \n \begin{array}{l} \n H_{0}: \mu_{L}=\mu_{S} \ \n H_{a}: \mu_{L}>\mu_{S} \n \end{array} \n \]