Answer:
4
Step-by-step explanation:
among 35 students 19 are taking history and so,
35 - 19
= 16.
among 16 students 12 are taking economics,
16 - 12
= 4.
the 5 students have been covered among the 31 students (19+12).
therefore, 4 is your answer.
hope it helps. :)
