A=El . bec c=1.0mg/L=1.0×103g/000mL =10×104g/100mL E1%=0,38/2,0×104=19×103 orE%=10g/M=11105155.85=19×103 cm3 c =1.0mg/L=1.0×10-3 g /1000mL = 1.0×10-4g/100mL b c 1% A = E1cm   1% m 4 3 1c - E = 0.38/2.0 10 = 1.9 10   1% 1cm 5 3 or E /M =10 =1.1 10 /55.85 =  1.9 10