\textbf{196.} In a Young's double-slit experiment, the path difference of light from the third dark fringe from the center is 1500 nanometers. In this experiment, the path difference of light from the second bright fringe is how many nanometers?
\[
\text{(1)}\ 800 \qquad \text{(2)}\ 1200 \qquad \text{(3)}\ 1600 \qquad \text{(4)}\ 1800
\]