[填空题]
A student measures a le2)n36tocf sgh qqf.+a ng9lwjc th8pr,6 th five times. All of the measurements 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.)