20 cm^2. Type in 20.
2*4 makes 8 divided by two makes 4. There are four sides so do 4*4 to make 16. 2*2 for the middle to make 4. 16+4 makes 20 cm^2
Answer:
The answer is 
Step-by-step explanation:
The value of the expression
is 
<h3>How to evaluate the sum?</h3>
The attachment represents the proper format of the question
The summation expression is given as:

Expand the radicands

Evaluate the square roots

Add the like terms

Hence, the value of the expression
is 
Read more about expressions at:
brainly.com/question/723406
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