David the shepherd boy faces Goliath the soldier in a battle. The only weapon David has is a slingshot which ejects a stone enough to incapacitate anyone being hit in the head. To effect a strong impact on its target, David must release the stone at angle of 30o and at a height of 0.2 m into the head of Goliath who is 2 m tall and 10 m away. With what initial velocity must David release the stone?

David the shepherd boy faces Goliath the soldier in a battle. The only weapon David has is a slingshot which ejects a stone enough to incapacitate anyone being hit in the head. To effect a strong impact on its target, David must release the stone at angle of 30o and at a height of 0.2 m into the head of Goliath who is 2 m tall and 10 m away. With what initial velocity must David release the stone?