Jada wants to know if students in middle school generally spend more time playing computer games than students in elementary school. She selects a random sample of size 20 from each population of students and asks them how many hours they played computer games last week. Suppose that the MAD for each of her samples is about 3 hours. Select all pairs of sample means for which Jada could conclude there is a meaningful difference between the two populations.

Group of answer choices

elementary school: 8; middle school: 15;

elementary school: 5; middle school: 11;

elementary school: 13; middle school: 10;

elementary school: 7; middle school: 12;

elementary school: 14 hours, middle school: 10 hours