Which of the following is an even function?

The perimeter of △cde is 55 cm. a rhombus dmfn is inscribed in this triangle so that vertices m, f, and n lie on the sides cd , ce , and de respectively. find cd and de if cf=8 cm and ef=12 cm. the answer is not cd=20 and de=15. i have tried that one, it does not work.

What is the probability of getting heads when flipping a coin and getting a number greater than or equal to 4 when rolling a single die?

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?