Geometry is my worst subject

The circumference of a circle is 5 pi cm. what is the area of the circle?

What two criteria are needed for triangles to be similar

Jamie went to home depot.she bought 25 bags of soil that cost $9 per bag.she bought 15 pots at $8 each,and she bought 23 bags of pebbles at $15 each.she used a coupon that gave her $5 off for every 100 dollars she spent.how much did jame pay at the end?