Cornet cable charge $32.50 a month for basic cable television. each premium channel selected costs an additional $4.95 per month. write an expression to find the cost of a month of cable service.
a.
32.50c + 4.95
c.
32.50 + 4.95
b.
32.50c + 2(4.95)
d.
32.50 + 4.95c

What stays constant in a given month?  The $32.50 charge.
What varies in a given month?  The number of $4.95 charges.

So no matter what happens, you always pay the $32.50 in a month.  Obviously, this is the constant, so this will be the constant term.  Which solutions have $32.50 as the constant term?  (c) and (d)

Now does $4.95 stay constant in a given month?  Read the question.  Obviously the amount you pay using this amount of money varies depending on how many premium channels you want.  So this is a varying term.  It will not be constant.  So (b) is not right.

The answer is (d).  $32.50 + $4.95 times the number of premium channels you want.