Answer:
23
21.7391304348 m
Explanation:
L = Initial length = 500 m
= Change in temperature = 40-(-35)
= Coefficient of thermal expansion = 
Change in length is given by
The change in length is 0.45 m
The number of joints would be
The number of joints is 23
Each bridge section length would be
The length of each bridge section would be 21.7391304348 m
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