Which of the following expressions is equivalent to [2x + 3(x + y)]- [a(x + y) - 2y]?
A) (1 -a)(x + y)
B) (5-a)(x + y)
C) 2x - 2y + (3 - a)(x + y)^2
D) 2x + 2y + (3 - a)(x + y)^2

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?

Can someone me do math because i am having a breakdown rn because i don’t get it

Diane’s bank is offering 5% interest, compounded monthly. if diane invests $10,500 and wants $20,000 when she withdrawals, how long should she keep her money in for? round to the nearest tenth of a year.