marie mixes 16 liters of 18% acid solution with a 27% acid solution which results in 21% acid solution. let x represent the number of liters of 27% solution used. which equation can be used to find the number of liters of 27% acid solution in the mixture?

A. 2.88+0.21x=0.27(x+16)

B. 2.88+0.27x=0.21(x+16)

C. 4.32+0.21x=0.27(x+16)

D. 3.36+0.27x=0.18(x+16)