Plz help me it’s multiple choice! mind showing work aswell?

Janet is mixing a 15% glucose solution with a 35% glucose solution. this mixture produces 35 liters of a 19% glucose solution. how many liters of the 15% solution is januet using in the mixture? a. 25 liters c. 28 liters b. 7 liters d. 10 liters

To determine the number of deer in a forest a forest ranger tags 280 and releases them back

The square root of 9x plus 7 plus the square rot of 2x equall to 7