<prompt> A 12-year-old child with Renal tubular acidosis type 1 is having muscle cramps and weakness. ECG shows all except?T wave inversion with U wavesST depressionHeart rate of 75 beats per minuteAbsent P waves  <response>: Ans. d Absent P waves.In hypokalemia, the ECG shows1. Increased amplitude and width of the P wave2. Prolongation of the PR interval3. T wave flattening and inversion4. ST depression5. Prominent U waves best seen in the precordial leads6. Apparent long QT interval due to fusion of the T and U waves long QU interval. 