Multivariable CalculusHardDouble Integrals ShareDouble Integrals · Hard problemEvaluate ∬R(3y+1) dA\iint_R (3 y + 1)\,dA∬R(3y+1)dA over the rectangle 0≤x≤1, 0≤y≤20 \le x \le 1,\ 0 \le y \le 20≤x≤1, 0≤y≤2. Express your answer as a common fraction or integer.Check Show answer Walk through it step by step Practice more like this Review this concept