Accurate prediction of total body water is critical in determining adequate dialysis doses for patients with renal disease. For African American males, total body water can be estimated by the function T(A, M, S) = -18.37 - 0.09A + 0.34M + 0.25S, where T is the total body water (in liters), A is age (in years), M is mass (in kilograms), and S is height (in centimeters).

(a) Find T(65, 85, 180).
(b) Find and interpret T_A(A, M, S), T_M(A, M, S), and T_S(A, M, S).