Question Dry bulk tanks: Answers Usually have low centers of gravity. Usually have high centers of gravity. Usually are not allowed to cross railroad tracks. Cannot be driven on interstates. Explanation Dry bulk tanks require special care when being driven because they have high centers of gravity. Drivers should also be careful because the materials being carried can easily shift in transit, causing a change in the vehicle's handling. This questions appears in the following tests: Delaware Class B Knowledge Test Florida Class B Knowledge Test Massachusetts Class A Knowledge Test Mississippi Bus Montana Class A Knowledge Test Montana Class B Knowledge Test New Jersey Class A Knowledge Test Wisconsin Class A Knowledge Test