A bag contains 56 marbles: 7 red, 8 green, 11 yellow, 17 brown, and 13 blue. If a marble is chosen at random, what is the probability that the marble is green?

A.1/5
B.1/6
C.1/7
D.1/8

Answer asap and if you do you will get brainliest. catherine buys a gallon of ice cream from the store. after taking it home, she eats a fifth of a gallon of ice cream. her sister eats some of the ice cream as well. if two-thirds of the original amount of ice cream is left, then what fraction of a gallon of ice cream did her sister eat?