After receiving complaints from readers, your campus newspaper decides to redesign its front page. A new format B is developed and tested against the current format, A. A total of 100 students are randomly selected, and fifty students are randomly assigned to each format condition. The students are asked to evaluate the effectiveness of the format on an 11 -point scale $(1=$ poor, $11=$ excellent $)$. Is the new format better than the current format?

a. State the null hypothesis.

b. What statistical test should you use?