<prompt> Hypokalemia ECG changes all exceptTall T waveProlonged QRS intervalDepressed ST segmentProminent U waves  <response>: In hypokalemia T wave is inveed; Hypokalemia plasma K -3.5 meqL- ST segment depression.A prominent U wave is now present immediately following the TThe actual QT interval remains 0.4 s.If the U wave is erroneously considered a pa of the T,a falsely prolonged QT interval of 0.6 s will be measured. Hypokalemia plasma K -2.5 meqL- The PR interval is lengthened to 0.32 s;the ST segment is depressed; T wave is inveed; a prominent U wave is seen.The true QT interval remains normal.Ref: Ganongs Review of Medical Physiology Twenty-Third Edition Page No:504 