______ are a specialized means of shipping petroleum, natural gas, and chemicals from sources to markets.
A) Air tunnels
B) Rail flatcars
C) Steam ships
D) Pipelines
E) Airlines
Answer: D) Pipelines
______ are a specialized means of shipping petroleum, natural gas, and chemicals from sources to markets.
A) Air tunnels
B) Rail flatcars
C) Steam ships
D) Pipelines
E) Airlines
Answer: D) Pipelines