What is the exponential regression equation that fits these data? A. y=12.11•1.36^x B. y=2.49x^2+7.29x+3.57 C. y=1.36•12.11^x D. y=4.89•1.47^x

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

Anyone know? will mark brainliest if you're correct!

Which of the following contains a variable?