C(r) is a circumference function. find c(5) when c(r)=6.28r

Need this asap if anyone can i would be very grateful. if you could show workings that would really

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50. write an inequality to determine the number of chores, c, janie could do to have enough money to buy the cd.

You wanted to draw an enlargement of design that printed on a card that is 4 in by 5