血漿中[ \mathrm{Na}^{+} ] = 138 meq/L; [ \mathrm{K}^{+} ] = 3.5 meq/L; [ \mathrm{Cl}^{-} ] = 114 meq/L; BUN 為14 mg/dL; Creatinine 為1.5 mg/dL，請計算其血漿有效滲透度（effective osmolality; mOsm/kg \mathrm{H}_{2}O）為何？
\mathrm{Na}^{+}
\mathrm{K}^{+}
\mathrm{Cl}^{-}
\mathrm{H}_{2}
276
281
285
290
