[填空题]
A student measures a length five times. Alq-614 jbxe oyll of the bs f yj:0 wyd1;q,ursc;iv44va l2 t/fmeasurements 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.)