Which equation correctly models the following situation: $x$ liters of 6% saline mixed with $y$ liters of 14% saline creating a 10 liter solution of 9% saline?

$\frac{x}{0.06}+\frac{y}{0.14}=\frac{10}{0.09}$ and $x+y=10$

$0.6x+1.4y=0.9\cdot 10$ and $x-y=10$

$0.06x+0.14y=0.09\cdot 10$ and $x+y=10$

$6x+14y=9$ and $x+y=10$