Answer:
The coefficient of linear expansion 
 \°C
\°C
Step-by-step explanation:
Given initial temperature 
 °C
°C
And final temperature 
 °C
°C
Initial length 

Final length 

We have to find the coefficient of linear expansion 
The coefficient of linear expansion is defined as the change in length per unit original length divide by the change in temperature. 

So, 
 \°C
\°C