Sandbox

$NSGAPA=({\frac {\sum ^{D}GDP_{R}}{\sum ^{D}POP_{r}}})-({\frac {\sum ^{G}DP_{r}}{\sum ^{L}POP_{r}}})$

<math>\frac{\operatorname d^2 R}{{\operatorname dQ}^2} < \frac{\operatorname d^2 C}{{\operatorname dQ}^2}</math\_>