If net charge on one object is doubled, then electric force will also get double. It is because they are directly proportional to each other.
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Answer:
B) The lightbulb uses 4,104,000 J more than the stereo.
Answer : The significant digit is 6
Explanation :
Multiply
by 
Now, on multiplying


Now, the significant digit is 6.
Hence, this is the required solution.