Answer:
[tex]C(r)=15+0.12r[/tex]
No option is correct.
Step-by-step explanation:
Modeling With Functions
The customer's monthly costs C expressed in dollars has two parts: one fixed cost regardless of the energy used ($15) and a variable cost (12 cents per kilowatt-hours). This can be expressed as 12/100*r = 0.12 r, being r the kilowatt-hours used. Joining both parts, we get the total cost expression as
[tex]C(r)=15+0.12r[/tex]
From the options presented, none of them can be called as correct, only the option d. is close enough to the real answer, but the variables z and c used are not accurate.
