=+43. Exercise 39 described a half-fraction of a factorial experiment in which the Nitsch’s trace elements factor was aliased with the highest-order interaction term. The response variable, antioxidant capacity, was measured in percent protection against singlet oxygen [O2(

1 Dg)]. The cited article reported the following data:

Temp pH Yeast Tryptone Nitsch %Prot 2 2 2 2 1 51.5 1 2 2 2 2 85.1 2 1 2 2 2 46.1 1 1 2 2 1 49.0 2 2 1 2 2 33.6 1 2 1 2 1 82.9 2 1 1 2 1 57.1 1 1 1 2 2 71.9 2 2 2 1 2 34.4 1 2 2 1 1 42.7 2 1 2 1 1 31.4 1 1 2 1 2 64.8 2 2 1 1 1 4.3 1 2 1 1 2 40.4 2 1 1 1 2 48.9 1 1 1 1 1 60.5