In a Chemistry Class, 6 Liters of a 4% Silver

Multiple Choice

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

A) 6 liters
B) 4 liters
C) 2 liters
D) 3 liters