Species a and b were separated using column chromatography. the elution time for species a (ta) was 200 s with a peak width (wa) of 35 s and the elution time for species b (tb) was 321 s with a peak width (wb) of 35 s. what length (in centimeters) should the column be if the theoretical plate height for species b is 1.0 mm?

length =