On September 12, 1966, astronauts conducted an experiment using ... ...

  On September 12, 1966, astronauts conducted an experiment using the second law of motion. A Gemini spacecraft (measured to be 3400 kg) connected with an orbiting rocket case. The thrusters were fired to provide a force of 890 N for 7.0 s. The change in velocity of the spacecraft and rocket case was found to be 0.93 m/s. What was the mass of the rocket case?
(A) 120 kg
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in 03. Laws of Motion