Solving questions using ven diagram

In the diagram below what is the approximate length of the minor arc ab

Ateacher asked his students to vote for an animal to be their class pet. five-eighteenths of the students voted for a rabbit, voted for a snake, and voted for a hamster. which statement is true? more students voted for a hamster than a snake. more students voted for a snake than a rabbit. more students voted for a rabbit than a hamster. more students voted for a snake than a hamster.

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