IMAS 2015 — Middle Primary Grades 3–4 — Round 2 Question 9

In the diagram, $E$, $F$, $G$ and $H$ are the respective midpoints of the sides $CD$, $DA$, $AB$ and $BC$ of a square $ABCD$. If the area of the square $KLMN$ is $4\ \mathrm{cm}^2$, what is the area, in $\mathrm{cm}^2$, of $ABCD$?