\(a,A=13\dfrac{2}{11}-\left(2\dfrac{3}{4}+9\dfrac{2}{11}\right)\\ =\dfrac{145}{11}-\left(\dfrac{11}{4}+\dfrac{101}{11}\right)\\ =\dfrac{145}{11}-\dfrac{525}{44}\\ =\dfrac{5}{4}\\ b,B=\left(7\dfrac{5}{9}+3\dfrac{7}{13}\right)-5\dfrac{5}{9}\\ =\left(\dfrac{68}{9}+\dfrac{46}{13}\right)-\dfrac{50}{9}\\ =\dfrac{1298}{117}-\dfrac{50}{9}\\ =\dfrac{72}{13}\)