Water was added to aqueous solution of a certain salt with concertation of 20%, which resulted in a 20% mass increase of the solution Part of the water was then evaporated from the resulting solution and its mass decreased by 20%. What is the current concentration of this solution?

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left

The parabola opens: y=√x-4 (principal square root) up down right left

Imogene invested $8,000 in a bank account that pays 8 percent simple interest at the end of each year. her friend invested the same amount in stocks where the growth of the investment is represented as 2,000 times the square root of 2 less than the time lapsed in years. if y1 and y2 represent the amount earned in dollars and t is the time lapsed in years, which system of equations correctly represents the situation?