Ineed the answer to 2a+b-a+3b it's in the maths section of my homework and i'm struggling to answer it

The graph represents the gallons of water in a water tank with respect to the number of hours since it was completely filled

Pleasse me i need an answer. give me the correct answer. answer if you know it ! the club will base its decision about whether to increase the budget for the indoor rock climbing facility on the analysis of its usage. the decision to increase the budget will depend on whether members are using the indoor facility at least two times a week. use the best measure of center for both data sets to determine whether the club should increase the budget. assume there are four weeks in a month. if you think the data is inconclusive, explain why.

Pamela has a 30-year, 5.75% mortgage on her $250,000 home. she has been paying on it for 5 years, and has recently hit some financial trouble. if her lender agreed to lower the interest rate on her $231,905.47 balance to 5.5%, what will her new payment be for the remainder of the loan?