What is six times the difference of a number is 9 and 18

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 .

The graph shows the amount of money noah earned based on the number of lawns he cut. which list shows the dependent quantities in the graph?

How many quarts of a 50% solution of acid must be added to 20 quarts of a 20% solution of acid in order to get a 40% solution of acid?