Expression 25: "S" Subscript, 1 , Baseline equals StartFraction, StartNestedFraction, 1 NestedOver "m" Subscript, 2 , Baseline , EndNestedFraction "N" Subscript, 1 , Baseline plus "N" Subscript, 2 , Baseline minus StartNestedFraction, 1 NestedOver "m" Subscript, 1 , Baseline , EndNestedFraction "M" Subscript, 1 , Baseline minus "M" Subscript, 2 , Baseline Over StartNestedFraction, 1 NestedOver "m" Subscript, 2 , Baseline , EndNestedFraction minus StartNestedFraction, 1 NestedOver "m" Subscript, 1 , Baseline , EndNestedFraction , EndFraction equals 4.7 3 2 0 5 0 8 0 7 5 7S1=1m2N1+N2−1m1M1−M21m2−1m1