The captain of a boat wants to travel directly across a river that flows due east with a speed of $1.00 \mathrm{~m} / \mathrm{s}$. He starts from the south bank of the river and heads toward the north bank. The boat has a speed of $6.10 \mathrm{~m} / \mathrm{s}$ with respect to the water. What direction (in degrees) should the captain steer the boat? Note that $90^{\circ}$ is east, $180^{\circ}$ is south, $270^{\circ}$ is west, and $360^{\circ}$ is north.