Two friends, Barbara and Neil, are out rollerblading. With respect to the ground, Barbara is skating due

Question:

Two friends, Barbara and Neil, are out rollerblading. With respect to the ground, Barbara is skating due south at a speed of 4.0 m/s. Neil is in front of her. With respect to the ground, Neil is skating due west at a speed of 3.2 m/s. Find Neil's velocity (magnitude and direction relative to due west), as seen by Barbara?