First let's find the area of the circle by using this equation:
(a = area, r = radius)
a = r²
a = 3²
a = 9
Now divide that by 4, so we can find the area of that quarter.
9/4 = 2.25
The answer 2.25 :)
Hope this helped! If you have anymore questions or don't understand, please comment on my profile or DM me. :)