Work out the circumference of a circle with diameter 1.8 cm

What is the inverse of the function f(x)=4x+8

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?

What is the range? can’t seem to find it out