Answer:
84
Step-by-step explanation:
f(1)=4^1 - 1 = 3
f(4) = 4^4 - 1 = 255
rate of change = 
(255 - 3) / (4 - 1) = 252 / 3 = 84
(-1,1.5) because you add both ys and both xs then divide by two to find the middle
Answer:
8 litres is roughly equivalent to 2 gallons, so 8 litres would be a lot more than 1 gallon. Hope this helps! :)