PLEASE HELP The way in which the areas of the world are grouped together for study is 1 distance decay
2 time-space compression
3 map scale
4 regions
5 scale of analysis

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?