According to the law of conservation of mass, which of these is true. a. when a physical change occurs, some of the mass is destroyed. b. when a chemical change occurs, some of the mass is destroyed. c. when both a physical and chemical change occurs, mass is added. d. when either a physical or chemical change occurs, no mass is destroyed. i also don't know which subject this would sorry

Asmall, positively charged ball is moved close to a large, positively charged ball. which describes how the small ball likely responds when it is released? it will move toward the large ball because like charges repel. it will move toward the large ball because like charges attract. it will move away from the large ball because like charges repel. it will move away from the large ball because like charges attract.

Around faucet handle is part of a(n) a. lever b. screw c. inclined plane d. wheel and axle

Avolcano erupts next to a grassland area in a valley. a. describe three ways in which material released by the volcano could impact the grassland area. b. describe three ways in which the grassland ecosystem could recover after a volcanic eruption.