Clearly, C and D sit opposite to each other. So, if A sits opposite to cook, B shall be the cook. Now, B is to the right of barber. So, one of the rest, say C will be barber. Clearly, then D on the opposite side shall be washerman or tailor. But, washerman is left of tailor and D on the left of A. So, D is washerman and A is tailor. Thus, A and B are Tailor and Cook.