What is chemical reaction?

Miner's coal distributors does not mine coal itself, nor does it even store or handle the coal. instead, miner's solicits orders for low sulfur coal from other firms, then purchases the required amount from suppliers and directs them to ship the coal to its customers. what is miner's

Acompound has a molecular weight of 12.124 atomic mass units and the empirical formula c3h40. what is the molecular formula of the compound?

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?