# Gravitation help..........thanks

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A projectile is shot directly away from Earth's surface. Neglect the rotation of Earth.
(a) As a multiple of Earth's radius RE, what is the radial distance a projectile reaches if its initial speed is one-fifth of the escape speed from Earth?
____ times RE

(b) As a multiple of Earth's radius RE, what is the radial distance a projectile reaches if its initial kinetic energy is one-fourth of the kinetic energy required to escape Earth?
_____ timesRE

(c) What is the least initial mechanical energy required at launch if the projectile is to escape Earth?

P.S.Bobpursley, sorry,I don't really understand the last question you answered....

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