1.2.3.4. Solution The number of observations per cell was: 3 Total df=23 Total observation = 24 Interaction Df=3 Df for amplifier and position are (1 and 3) any order Number of factors for amplifier and position = (2 and 4) any order Observations per cell = 24/(2*4) =3 Two-factor ANOVA with replication The two factors are PVC and Temperature. Each cell having 3 observations or replications..