Researchers at a university with an enrollment of 12,000 take a census of the entire student population,

Question:

Researchers at a university with an enrollment of 12,000 take a census of the entire student population, asking, “Shoplifting is not only illegal, it raises the prices that we all have to pay. Have you ever shoplifted from the university bookstore?” Based on the preceding, discuss the possible presence of
(a) Sampling error and
(b) Nonsampling error.