Answer:
I believe the correct answer is option B
Answer: 19 years
Step-by-step explanation:
Given
Amount invested 
Rate of interest 
after 1-year amount becomes

After n years it is

Sum accumulated is 

Steps:
5.15*1.09*12 = total
5.6135*12 = total
$67.36= total
Answer: $67.36
Answer: I gave the evaluate answer and the differentiate w.r.t x answer. Sorry for caps.
Step-by-step explanation: EVALUATE x4n−3
DIFFERENTIATE W.R.T. X (4n−3)x4(n−1)
The answer is 5 gallons
Its very simple.
Turn 60% and 10% into decimals ( .60 and .10)
Multiply 8 gallons ( brand A ) by .60 and you get 4.8 gallons
Multiply 2 gallons ( brand B ) by .10 and you get .2 gallons
Add them up and you get 5 gallons.