104.3f.

Each of the hybrid mana symbols represents a cost that can be paid with one of two colors: {W/U} in a cost can be paid with either white or blue mana, {W/B} white or black, {U/B} blue or black, {U/R} blue or red, {B/R} black or red, {B/G} black or green, {R/G} red or green, {R/W} red or white, {G/W} green or white, and {G/U} green or blue. A hybrid mana symbol is each of its component colors.

Example: {G/W}{G/W} can be paid by spending {G}{G}, {G}{W}, or {W}{W}.