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2.m(H2O)=200-4=196г; w = 4/200=0,02 = 2%

3. m р-ра = 495+5=500г; w=5/500=0,01=1%

4. m(соли)=100-94=6 w=6/100=0,06=6%

5.m(р-ра)=3*10=30г m(H20)=30-3=27г

6. m(р-ра) =(23/(100-8))*100=0,25*100=25г; m(соли)=25-23=2г