I think the answer is A too 
        
             
        
        
        
Answer:
Why
Explanation:
He showed because he had changed the era of using lamps and to use light bulbs he and his fellow scientist.
I hope it helps :D
 
        
             
        
        
        
Answer:
Although Adams was initially enthusiastic about the presidential mansion, he and Abigail soon found it to be cold and damp during the winter. Abigail, in a letter to a friend, wrote that the building was tolerable only so long as fires were lit in every room.
Explanation:
 
        
             
        
        
        
Answer:
2x+5y=10 
Explanation:
y= -2/5x+2
convert into standard form
-2/5x+y=2
2x+5y=10
 
        
             
        
        
        
Signposts, internal previews and internal summaries are examples of linking statements.
<h3>What are signposts, internal previews and internal summaries?</h3>
The signposts, internal previews and internal summaries are a tool that allows the readers or audience to connect and understand the ideas that the speaker is using in his speech.
According to the above, it can be inferred that these tools are linking statements that help connect one thought to another in a speech.
Learn more about Signposts in: brainly.com/question/9374047
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