Interpret the following iterated integrals as double integrals over a domain D. Sketch D and change the order of integration
(a) ∫∫ f(x,y) ∈[0,3] ∈[0,√3] dy dx
(b) ∫∫ f(x,y) ∈[1,3] ∈[0,in x]dy dx
(c) ∫∫ f(x,y) ∈[0,1] ∈[arctan y,π/4] dx dy
(d) ∫∫ f(x,y) ∈[√-2,√2] ∈[y2-1,1] dx dy