what are Similarities Between Eating Clean to Prevent a Heart Attack and Keeping Drains Clean to Prevent Clogged Pipes

first one is the correct answer

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.