5. The diagram shows four overlapping hearts. The areas of the hearts are $1 \mathrm{~cm}^{2}, 4 \mathrm{~cm}^{2}, 9 \mathrm{~cm}^{2}$ and $16 \mathrm{~cm}^{2}$. What is the total shaded area?
A $9 \mathrm{~cm}^{2}$
B $10 \mathrm{~cm}^{2}$
C $11 \mathrm{~cm}^{2}$
D $12 \mathrm{~cm}^{2}$
E $13 \mathrm{~cm}^{2}$
5. B Since the areas of the four hearts are $1 \mathrm{~cm}^{2}, 4 \mathrm{~cm}^{2}, 9 \mathrm{~cm}^{2}$ and $16 \mathrm{~cm}^{2}$, the outer and inner shaded regions have areas $16 \mathrm{~cm}^{2}-9 \mathrm{~cm}^{2}=7 \mathrm{~cm}^{2}$ and $4 \mathrm{~cm}^{2}-1 \mathrm{~cm}^{2}=3 \mathrm{~cm}^{2}$ respectively. Therefore the total shaded area is $7 \mathrm{~cm}^{2}+3 \mathrm{~cm}^{2}=10 \mathrm{~cm}^{2}$.