Given a = {x | x < 1}, b = {x | x ≥ 5}, and c = {x | x = 5}, match the following items.
1.a∪b ( ){x | x = 5}
2.a∪c ( ){x | x < 1 or x = 5}
3.b∪c ( ) {x | x < 1 or x ≥ 5}
4.a∩b ( ) ø
5.b∩c ( ){x | x ≥ 5}

An energy drink company claims that its product increases students' memory levels. to support its claims, the company issues advertisements claiming that 8 out of 10 people (chosen randomly from across the country) who tried their product reported improved memory. the missing component in this study is a .