In the sequence 5, 10, 15, 20, 25, 30, how many times does the number 15 occur?

A. 1

B is ranked 5th from the bottom in a group of 25 people. What is B's rank from the top?

C. 19TH

E is ranked 12th from the top and 9th from the bottom in a competition. How many participants are there in total?

B. 21

In a class of 30 students, A is ranked 12th from the top. What is A's rank from the bottom?

B. 19TH

In the sequence 10, 20, 30, 40, 50, how many times does the number 30 occur?

A. 1