Does anyone know how to do the checking part? I've got everything else down but I don't know how to do the checking part.

Which is a reasonable estimate of the amount of water in a small, inflatable pool used by children?

Fanny mendelssohn manages all the magazines and paperback books at a local grocery store. she prices many paperbacks to sell at $7.99. the cost to the store is $5.29. what is the markup rate on a paperback book, based on its cost?

What is r i 4.5+10r=-6.5 with work pls