Y challenge 20
Line l is the perpendicular bisector of AC, and D is any point on l.
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Аа
D
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arity
С
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Complete the proof that a point on the perpendicular bisector of a line segment is equidistant from the
segment's endpoints.
Hint: We need to show that the distance between A and D is the same as the distance between C and D.
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Statement
Reason

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?