The ratio of the radii of two circles is 4: 5. what is the ratio of the circumferences of the two circles?

Fiona joins a fruit of the month club. the entry cost was $25 and then she pays $18 per month. if she participates for 8 months, how much will she pay in all? how much in 10 months?

What is the smallest integer n such that n\sqrt{2} is greater than 20

If you shift the linear parent function, f(x)=x, up 13 units, what is the equation of the new function?