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Answer:
25[tex]\pi[/tex]
Step-by-step explanation:
[tex]\pi[/tex][tex]r^{2}[/tex]=area of circle
[tex]\frac{1}{4}[/tex][tex]\pi[/tex][tex]r^{2}[/tex]=1/4 of the area of a circle
now solve
[tex]\frac{1}{4}[/tex][tex]\pi[/tex][tex]10^{2}[/tex]
[tex]\frac{1}{4}[/tex][tex]\pi[/tex]100
25[tex]\pi[/tex]