[填空题]
A student measures a length five9,hs)o 5bzo oq times. All of the measurementsd7)o n481 t x mibtxz+c7kps)u 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.)