<span>Heavy metals like mercury enter waterways by industrial dumping and poor regulatioin of effluent, and they also enter soil through a similar manner, in which waste is disposed of imporperly. Another source of heavy metals are the gases leaving industry carrying these metals. The metals fall as a solid on to soil and water ways. Therefore, the answer is D.</span>
I’d say market and distribution would be the next step
Bubbles, release of gas, change in color, release of a smell, change in temperature, formation of a precipitate,
