The cumulative frequency
(Fig. 4a) shows that 50% of carrot cells subjected to the ultrasound
at a frequency 21 kHz had the area of 0.0056 mm2 (5626 lm2) for
samples treated for 10 min, 0.0042 mm2 (4165 lm2) for 20 min
and 0.0161 mm2 (16,140 lm2) for 30 min.