A large iron sphere was placed a certain from a huge boulder. The force of gravity felt by the sphere from the boulder is 0.2N. The mass of the boulder is doubled and the distance is doubled. Which statement is correct?

the total distance that martina travels that day is

(distance from home to mom's office) plus (distance from mom's office to school)

plus (distance from school to library) plus (distance from library to friend's house)

plus (distance from friend's house to martina's house).

(we don't know what any of these distance actually is.)

conservation of mass

mass before something happens = mass afterwards