Your mass is 80 kg on Earth. What would your MASS be on Planet Roethler, which has twice as much
gravity as on Earth?
40 kg
160 kg
80 kg

Mass doesn't change. It doesn't matter where you are.

If your mass is 80 kg when you're on Earth, then your mass is 80 kg. It doesn't matter where you are, where you used to be, or where you're going tomorrow.

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.