#2 - A metal railing rusting in camp weather. Rusting is a chemical change.
The statement is constructed with the purest form of veracity, and
it is True in every respect, every jot and tittle, ever 'p' and 'q'.
Truer words are rarely if ever spoken. Verily and forsooth,
Most comets indeed come from a dark, distant, foreboding
place in the solar system, unknown until very recently, and
now referred to as the "Oört Cloud".
It is fiery because it is cooled molten magma
It would <span>keep rolling without slowing down if no friction acted upon it.
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Because they burn fossil fuels, and in this process large amounts of polluting gases (such as carbon dioxide, sulphure dioxides, nitrogen oxides) are released into the atmosphere. Carbon dioxide is especially problematic, because it is a greenhous gas: most of it cannot be re-absorbed by natural processes therefore increasing the global warming effect.