What other fossil fuel is a byproduct of petroleum drilling? a. nuclear b. coal c. natural gases d. biomasswhat other fossil fuel is a byproduct of petroleum drilling? a. nuclear b. coal c. natural gases d. biomass

Why might surface mining be less risky for miners than underground mining? a. surface miners can become trapped in a collapsed mine. b. surface miners work in dusty, enclosed areas. c. surface miners work aboveground. d. surface miners use elevators to enter mines.

Is a hamster and guinea pig part of the same species ?

Based on the results of this study, what questions remain unanswered? how can these questions guide future research