I will leave out the base, b since it's the same for all these logarithms.

So are the bottom numbers the answers? Becasue if the top are the questions then gallon would be largest, 2pt, then 0.95 liter If this doesn't help let me know because the problem doesn't look complete. Let me know!
A/B = 11/15 OR 15 x A = 11.B OR B= 15A/11
Actual Gallons in A = 550 x 66 % = 363 gal
Total capacity of B = 15A/11 OR (15 x 550)/11 = 750 gal.
Actual Gallons in B = 750 x 53% = 397.5 gal
Negative rate of change just means that the graph is falling. On this one, that's everywhere after x=0.5. The only choice that's completely in that section is the last one.