[填空题]
A student measures a length five times. A frf3.mq3. 8eyrii zu rmlj+/1ll of the p qgnp6* fb,,nmeasurements lie between $18.8 \mathrm{~cm}$ and $19.2 \mathrm{~cm}$. What should the student quote as the absolute uncertainty in the length? The absolute uncertainty is $cm$ (please only input numerical value without units and without the $\pm$ symbol.)