Question

There are 20 students in a chemistry class and 30 students in a p are to be enrolled in both the courses, then the number of students w mistry class and 30 students in a physics dass Men students er ere class or chemistry class is (A) 50. if two classes meet at the same hour (B40 H two classes meet atometer (C) both (A) and (B) correct (D) (A) correct but (B) incorrera 42. Let R be relation defined by R = f(a, b) az b, a,ber). Then R, is

Answer 1