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Answer:
it can't pe proven ..... is the right answer of this question...
CD=50 DVD=40
5C+7D=530
C=D+10
C-D=10
Solve the system
5C+7D=530
5C-5D=50 (multiply by 5)
Subtract
12D=480
D=40
Substitute in any of the equations
C-D=10
C-40=10
C=50
.05ml of the solution is calcium