Find the surface area of a cone with a diameter of 18 cm and slant height of 24 cm. Use 3.14 for pi. Plz help

Quick translate "x is 12 units from 20" into an equation. what are the values of x being described? if you can answer any of my other questions that'd be great too

What’s the range cuz i can’t find it?

Julia bought 7 hats a week later half of all her hats were destroyed in a fire. there are now only 12 hats left with how many did she start