By adding up all the individual forces of the object
This is a bit too broad. Maybe this is something to google up
Answer:
1.38*10^18 kg
Explanation:
According to the Newton's law of universal gravitation:

where:
G= Gravitational constant (6.674×10−11 N · (m/kg)2)
ma= mass of the astronaut
mp= mass of the planet

so:

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<span>The
best and most correct answer among the choices provided by the question is B.
Reaches a max height of
8.25 feet after 0.63 seconds</span>
.
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</span><span>Hope my answer would be a great help for you. </span> </span>
<span> </span>