All but B, as on B an a can be factored out
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Given information
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Area = 40ft²
Length = √20 ft
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Formula
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Area = Length x Width
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Find Width
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40 = √20 x width
Width = 40 ÷ √20
Width = 40 ÷ 2√5
Width = 20 ÷ √5

R= diameter/2
answer: 8 units
Answer:
900
Step-by-step explanation:
Hope this helps!