Answer:
c) Both the parts will weigh the same
Explanation:
center of gravity is based on weight so if you cut down the center of gravity you would have 2 equal parts
(might be D if it is cutting against the center of gravity)
 
        
             
        
        
        
As the metal expands as does the road bed so neither really effevts those foing over the bridge. as it is hot the metal will expand and so will most tarmac on roads.
        
             
        
        
        
Not 100% but i think it'll cause the earth to rotate slightly slower, its definitely not the last one though