Carl wrote this expression to describe the total dues he has left to pay.

y – 15

which situation could be described by this expression?

a.
carl knows he has to pay $15 in dues. he does not know how much he has paid.

b.
carl knows he owes $15 in dues. he does not know how much he has paid so far.

c.
carl knows he has to pay $15 in dues. he does not know how much he has left to pay.

d.
carl does not know how much he has to pay in dues. he does know that he has paid $15 so far.