A slingshot obeying Hooke’s law is used to launch pebbles vertically into the air. You observe that if you pull a pebble back 20.7 cm against the elastic band, the pebble goes 6.3 m high.

Part A Assuming that air drag is negligible, how high will the pebble go if you pull it back 41.4 cm instead? Express your answer to two significant figures and include the appropriate units.

Part B How far must you pull it back so it will reach 12.6 m ? Express your answer to three significant figures and include the appropriate units.

Part C If you pull a pebble that is twice as heavy back 20.7 cm , how high will it go? Express your answer to two significant figures and include the appropriate units.