[填空题]
When doing a physical experiment, Peter measures the mass of a;r/kd. ci)2 eieol(hgn object ten times. he(c2i;igkol)r/deilq ,;dj/ cnha met,+t7iyj -6. ,7+tdm,j6e/achi-;q t y jilnAll of the measurements lie between $49.8 \mathrm{~g}$ and $50.2 \mathrm{~g}$. What should him quote as the absolute uncertainty in the mass? $\pm$ $g$ (Only put numerical value in the blank without any units or signs)
