Answer is C. Granted gas prices are fixed. if you buy 1 gallon.. price is x. if you buy 2 gallons, price is 2x. and so on. constant rate of change.
Given:
The local rate for electrical service is 6 cents per kilowatt-hour.
We need to know how much money would be saved in a year by using a dishwasher 4times per week rather than 6 times per week
From the table:
The cost of using a dishwasher 4 times per week = $29
The cost of using a dishwasher 6 times per week = $44
So, the saving will be = 44 - 29 = 15
So, the answer will be $15
Average rate of change can be calculated by determining the
rate of change at x = a, and at x = b
f’(x) =2 (3^x) ln(3)
f’(0) = 2 ln(3)
f’(1) = 6 ln(3)
f’(2) = 18 ln(3)
f’(3) = 54 ln(3)
Average:
at section A = [6 ln(3) – 2 ln(3)]/1 = 4 ln(3)
at section B = [54 ln(3) – 18 ln(3)]/1 = 36 ln(3)
section B is 9 times larger.
Based from the f’(x), f’(x) varies as the power of x. so the
greater of value of x, the greater the rate of change.
