For the Following Systems of Equations in Echelon Form, Tell $$\begin{array}{r}x+3 y+4 z=80 \\4 y+5 z=40\end{array}$$

Multiple Choice

For the following systems of equations in echelon form, tell how many solutions there are in nonnegative integers.
- $$\begin{array}{r}x+3 y+4 z=80 \\4 y+5 z=40\end{array}$$

A) 2
B) 4
C) 3
D) 5