单项选择题
A.Thimble Shoal Main Channel or the South Auxiliary Channel
B.Any of the channels but keep to the right hand side
C.The South Auxiliary Channel
D.Thimble Shoal Main Channel
单项选择题 After you enter the Ohio River at Cairo，which span of the Illinois Central RR Bridge would you select to pass under? （）
单项选择题 After you enter the Ohio River at Cairo，the Map shows that the deepest water under the Illinois Central RR Bridge would be found under which span? （）
单项选择题 After the passage of a cold front the visibility（）.