Answer:
Rate of change of area will be 
Explanation:
We have given rate of change of radius 
Radius of the circular plate r = 52 cm
Area is given by 
So 
Puting the value of r and 

So rate of change of area will be 
An amplifier.
Electrical energy provided to an amplifier is converted into sound energy as it is "fed" or provided to the speaker portion of an amplifier.
I think it was by boat and coming from over seas
Answer:
A shorter than the original source and in the researcher's words
Explanation:
The summary is an abridged version of the original source and in the researcher's own very words.
Summaries gives an over-arching perspective and excludes implicit details from a given text.
A summary should not be detailed and must avoid overt illustrations. They must capture the true essence of piece leaving out flowery details.
A summary should be lesser in length than the original piece. Any third party reader should immediately be able to grab the details of the original piece from the summary.