I am guessing there are a few parts to this question;
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At lift-off- the acceleration due to gravity is 9.8ms^-2
To work it out to equal 9.8ms^-2
g= G X (mass of Earth / Radius of Earth^2)
G= 6.67X10^-11 Mass of Earth = 5.97X10^24 Radius of Earth = 6.3X10^6)
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