Which expression is equivalent to sq root of -80

Hunter designs two flags for his adventure club. what is the length of the base, x, of the larger flag? enter your answer, as a decimal, in the box.

Mary used 1/7 of a spool of ribbon to complete 4 projects. she used the same amount of ribbon on each project. how much ribbon did she use on each project?

At a sale this week, a desk is being sold for $213. this is a 29% discount from the original price. what is the original price?