Rows — In a row of 30 students facing North, what is R's position from the left end? Statements: I. There are 12 students between R and Q. II. T is 10th from the right end; there are 16 students between T and R.

Introduction / Context:
Compute an absolute position using a fixed-size row and separations.

Given Data / Assumptions:

• Total = 30 students.
• I: Only distance between R and Q (no anchors).
• II: T is 10th from right; 16 between T and R.

Concept / Approach:
Convert T's right-rank to a left-rank, then apply the 'k between' offset (k+1) and validate side feasibility.

Step-by-Step Solution:

Verification / Alternative check:
Bound checks ensure only the left-side placement is feasible, giving a unique result.

Why Other Options Are Wrong:

• A/C/D/E: II alone already yields a unique position.

Common Pitfalls:
Forgetting to test both sides; forgetting the +1 offset.

Final Answer:
B — Statement II alone suffices (R = 4th from left).