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Trancorp currently transports all its goods to Burland
Island by truck. The only bridge over the channel separating Burland from the mainland is congested, and trucks typically spend hours in traffic. Trains can reach the channel more quickly than trucks, and freight cars can be transported to Burland by barges that typically cross the channel in an hour. Therefore, to reduce shipping time, Trancorp plans to switch to trains and barges to transport goods to Burland.

Which of the following would be most important to know in determining whether Trancorp's plan, if implemented, is likely to achieve its goal?
A: Whether transportation by train and barge would be substantially less expensive than transportation by truck.
B: Whether there are boats that can make the trip between the mainland and Burland faster than barges can
C: Whether loading the freight cars onto barges is very time consuming.
D: Whether the average number of vehicles traveling over the bridge into Burland has been relatively constant in recent years?
E: Whether most trucks transporting goods into Burland return to the mainland empty?