Numerical answer type, tolerance 0.5.
Answer: 19
Enumerated: monosubstituted benzenes with C2H5O (2-phenylethanol, 1-phenylethanol, ethoxybenzene, benzyl methyl ether) = 4; disubstituted with {CH3, CH2OH}, {CH3, OCH3}, {C2H5, OH} at o/m/p = 3 x 3 = 9; trisubstituted dimethylphenols = 6. Total 4 + 9 + 6 = 19.