Mass, if you know what element you are working with.
Answer:
A
Explanation:
Your answer would be A because Earth is formed from cold gases collapsing due to gravity. The Solar System was formed when a huge amount of dust and gas began to collapse under its own gravity, and as the cloud collapse it started to spin causing the material within the cloud to gather into a swirl and then formed into planets and as the planets are formed they kept this spinning motion.
It really depends on the 'type' of rock it is. By this I mean whether it's impermeable or permeable. Impermeable rocks don't allow water through and permeable rocks do. It has to do with how 'porous' a rock is: how many openings it has and how spaced apart are its particles are. Sandstone is permeable and Shale impermeable.
Answer:
Barium Di-chloride (BaCl^2). H^2 is released as a by-product in the form of a gas.
Explanation:
Communication will be the answer
