[填空题]
A student measures a .oc qjq.,s;pf)z*/ kyse3u y clength five times. All of thz4p605r ly - ;axoiysae 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.)