Are my answers here correct ?

Research questions for z test, t test for independent samples and t test for dependent samples :

z test: "An investigator is interested in finding out whether the particular sample of college students is similar to or different from college students in general.

t test for independent samples: "Do 11th graders have significantly more unexcused absences than 10th graders in junior highs?

t test for dependent samples: " Do people drop weight after attending a weight loss boot camp for 2 months?