Seattle City Light ¹ charges residents for electricity on a daily basis. There is a basic daily charge of 15.70 cents. In addition, for each day the first 10 kWh cost 4.66 cents per kWh and any additional kWhs are 10.71 cents per kWh. (A kWh is a unit of energy.)

a) Complete the table below which shows the cost in dollars of usage from 0 to 40 kWh in increments of 5 kW

kWh: 0, 5, 10, 15, 20, 25, 30, 35, 40,

Cost in dollars: for each kWh

b) Write a piecewise-defined function to describe the usage rate.

Enter the exact answer in terms of dollars.

C (n) = ...... for 0 less than and equal to n less than and equal to 10

C (n) = .... for n > 10

c) What is the cost for 38 kWk?

d) How many kWh can you burn on a day for $4?