What is the center of a circle whose equation is x2 + y2 - 12 x - 2 y + 12 equals 0

(-12,-,-,,2)

In a fifth grade class, 3/5 of the girls have brown hair. of the brown-haired girls, 3/4 of them have long hair. of the girls with long brown hair, 1/3 of them have green eyes. what fraction of the girls in the class have long brown hair?