1A. Solve the system of equations

$$
\left\{\begin{array}{l}
x \sqrt{x}+27 y \sqrt{x}=36 \\
27 y \sqrt{y}+9 x \sqrt{y}=28
\end{array}\right.
$$
$$
\begin{aligned}
& \left\{\begin{array} { l } 
{ x \sqrt { x } + 27 y \sqrt { x } + 27 y \sqrt { y } + 9 x \sqrt { y } = 64 } \\
{ 27 y \sqrt { y } + 9 x \sqrt { y } - x \sqrt { x } + 27 y \sqrt { x } = 8 }
\end{array} \Leftrightarrow \left\{\begin{array}{l}
(\sqrt{x}+3 \sqrt{y})^{3}=64 \\
(\sqrt{x}-3 \sqrt{y})^{3}=8
\end{array} \Leftrightarrow\right.\right. \\
& \left\{\begin{array} { l } 
{ \sqrt { x } + 3 \sqrt { y } = 4 } \\
{ \sqrt { x } - 3 \sqrt { y } = 2 }
\end{array} \Leftrightarrow \left\{\begin{array}{l}
\sqrt{x}=6 \\
\sqrt{y}=\frac{1}{3}
\end{array} \Leftrightarrow\right.\right.
\end{aligned} \Leftrightarrow\left\{\begin{array}{l}
x=36 \\
y=\frac{1}{9} .
\end{array}\right.
$$