(b) what is the volume percent % (v/v) of an alcohol solution made by dissolving 135 ml of isopropyl alcohol in 745 ml of water? (assume that volumes are additive.)

Volume percentage is the percentage of volume of interested compound from the whole volume of the solution.
volume percentage of isopropyl alcohol can be calculated as follows;
volume percentage (v/v%) = volume of alcohol/ total volume of solution x 100%
total volume = 135 + 745 = 880 mL
substituting the values ,
v/v % of alcohol = 135 mL / 880 mL x 100 %
answer = 15.34 %

y= -2 + 1/(3+x)

If you want to check just plug it into a graphing calculator.