Answer all the questions below and press submit to see how many you got right.
Center : The center of a circle is the unique point in the circle, such that all points on the boundary of the circle have a constant distance equal to the radius from that point. The center of a regular polygon is the point that has equal distance from all its corners.
Which of the following is the best move for white in the position?
Combination : In combinatorics a combination is a selection of a subset from a set. There are $\binom{n}{k}$ different combinations that choose $k$ objects out of $n$ possible objects. For example if there is a league with 5 soccer teams, there are $\binom{5}{2}=\frac{5!}{3!2!}=10$ different possible match-ups. In chess a combination is a series of moves that results in a material or positional gain.
What is the best move for white in the position?