As part of a study to determine the effect of flaxseed on blood thiocyanate concentration in rats, the authors reported the amount of hydrogen cyanide (HCN) in the flaxseed fed to the rats. This value was reported to be 255 ± 8.3 mg/kg seed. Based on the authors' intent to communicate that flaxseed source is fairly consistent in its HCN content; do you think these values represent mean ± SD or mean ± SE?