The article “Production of Gaseous Nitrogen in Human Steady-State Conditions” (J. Applied Physiology, 1972:

155–159) reports the following observations on the amount of nitrogen expired (in liters) under four dietary regimens:

(1) fasting, (2) 23% protein, (3) 32% protein, and (4) 67%

protein. Use the Kruskal–Wallis test at level .05 to test equality of the corresponding is.