At what level in the tracheobronchial tree are cilia completely absent?

A scientific approach to research in which a researcher controls, manipulates, and then measures one or more variables to ascertain how manipulating the variables affects the subjects is called ______________ research.

A) prospective B) qualitative C) experimental D) nonexperimental

Which of the following is NOT a true statement regarding patients with end-stage renal disease?

a. Kidney failure has a reputation for being a gentle death. b. Patients urine output increases. c. Patients with some urine output may live for months after stopping dialysis. d. Patients with no urine output are likely to die within a week or two.