premise: fossil fuel is a kind of fuel sent2: a mine produces minerals sent3: mining is when humans take rocks and minerals from the ground sent4: a source of something emits / produces / generates / provides that something sent5: the ground is part of the earth sent6: coal is a kind of fossil fuel sent7: fuel is a kind of energy source sent8: a coal mine is a source of coal under the ground sent9: a coal mine is a kind of mine.
hypothesis: coal can be mined from the earth and used as an energy source