Without plotting find a point on the graph of x+y=21 whose y coordinate is three more than the x coordinate

Name the most appropriate metric unit for each measurement like the mass of cow

Find the height of a square pyramid that has the volume of 32 ft.³ and a base lengthof 4 feet

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?