GATE | CS | 2012 | Databases | Relational Algebra | Question 50

Consider the following relations A, B, C. How many tuples does the result of the following relational algebra expression contain? Assume that the schema of A U B is the same as that of A. 

Table A
Id   Name    Age
----------------
12   Arun    60
15   Shreya  24
99   Rohit   11

Table B
Id   Name   Age
----------------
15   Shreya  24
25   Hari    40
98   Rohit   20
99   Rohit   11

Table C
Id   Phone  Area
-----------------
10   2200   02  
99   2100   01