Respuesta :

Answer:

78.5398

Step-by-step explanation:

Area of a circle:

a=[tex]\pi[/tex]r²

Radius is 10.

a=[tex]\pi[/tex]10²

a=[tex]\pi[/tex]100

a=314.15926

90° is one quarter of the circle, so multiply it by 0.25.

314.15926x0.25=78.5398

I don't know how many places the directions want it rounded to.  If it said to use 3.14 for pi, the answer would just be 78.5.