A region R is shown. Decide whether to use polar coordinates or rectangular coordinates and write JR f(x, y) dA as an iterated integral, where f is an arbitrary continuous function on R. 10 R 8 0 8 10 x on x , v ) dy dx 10 f (r , @ ) r dr de O 18 f(r cos(0), r sin(0)) r dr de 2 It 10 Jo f(r cos(0), r sin(0)) r dr de