The following dot plot represents student scores on the Unit 1 math test. Scores are in whole number increments. If the test was out of 20 points, about what percentage of the students scored at least 80% on the test?

17%
48%
67%
12%

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 .