In a Chemistry Class, 6 Liters of A $4 \%$ - Saline Solution Must Be Mixed with A

Multiple Choice

In a chemistry class, 6 liters of a $4 \%$ - saline solution must be mixed with a $10 \%$ solution to get a $6 \%$ solution. How many liters of the $10 \%$ solution are needed?

A) $6.0 \mathrm{~L}$
B) $4.0 \mathrm{~L}$
C) $2.0 \mathrm{~L}$
D) $3.0 \mathrm{~L}$