Can someone me on that one ? an advance ? don't forget to show your work : )

How many liters of peroxide should be added to 12 liters of an 8% peroxide solution so that the resulting solution contains 16% peroxide?   original added new amount of peroxide 0.96 liters x 0.96 + x amount of solution 12 liters x 12 + x 0.18 liter 1.14 liters 1.92 liters 2.10 liters

Determine the function’s value when x = -1 a. g(-1)=-3 b. g(-1)=0 c. g(-1)=1 d. g(-1)=27

Taina went to the toy store and spent $21.05 on a board game, $2.75 on coloring books, and $13.22 on a model airplane. about how much money did taina spend in the toy store?