Yang is making new cushion covers for a chair. There are three sizes of cushions on the chair. What is the surface area of the arm rest cushion?​

chemists are often responsible for designing a chemical reaction and analyzing the products obtained from it. one significant part of designing a chemical reaction is determining the amount of each reactant that is needed and the amount of each product that will be produced. in order to do so, chemists use stoichiometry, the quantitative relationships between reactants and products.

24

step-by-step explanation:

you just have to add the 15 + 9 to get 24

you do this bc you want to find the total of the whole line and those two numbers make up the line