Atomic emission spectroscopy and the method of standard addition are used to determine the Na* concentration and its uncertainty in an unknown sample. Increasing amounts of a 1.75 ug/mL standard Na* solution are added to a series of volumetric flasks containing 10.00 mL of the unknown solution. The volumetric flasks are then diluted to a final volume of 200.0 mL. Atomic emission spectroscopy is then used to measure the emission intensity of each solution. Unknown Volume (mL) Standard Volume (mL) Final Volume (mL) Emission Intensity 10.00 0.00 200.0 352.0 10.00 5.00 200.0 495.0 10.00 10.00 200.0 643.0 10.00 15.00 200.0 808.0 10.00 20.00 200.0 949.0 Based on the data in the table above, determine the original concentration of Na* as well as its uncertainty in the unknown sample. Report the uncertainty with three significant figures. Concentration Uncertainty Number Number 1.4 g/ mL 0.002 ug/ mL