Hi, I need some help solving this problem, I'm trying to prepare for an exam. Thanks

Let the result of a random experiment be classified as one of the mutually exclusive and exhaustive ways A1, A2, A3 and also as one of the mutually exclusive and exhaustive ways B1, B2, B3, B4. 200 independent trials of the experiment result in the following data:

----B1 B2 B3 B4
A1 |10 21 15 6
A2 |11 27 21 13
A3 | 6 19 27 24


Test at the 0.05 level, the hypothesis of independence of the A attribute and the B attribute, namely H0: P(Ai intersect Bj) = P(Ai)P(Bj), i=1,2,3 and j=1,2,3,4, against the alternative of dependence.