Required information
Margaret walks to the store using the following path: 0.650 mi west, 0.420 mi north, 0.110 mi east. Assume north to be along the $+y$-axis and west to be along the $-x$-axis.
Find the direction of the displacement vector. Enter the answer as an angle north of west north of west

Step 1 ：Margaret walks to the store using the following path: 0.650 mi west, 0.420 mi north, 0.110 mi east. We assume north to be along the +y-axis and west to be along the -x-axis.

Step 2 ：We represent each of these steps as vectors: west = [-0.65, 0], north = [0, 0.42], east = [0.11, 0].

Step 3 ：We add these vectors together to get the total displacement vector: total = [-0.54, 0.42].

Step 4 ：We find the direction of this vector using the arctangent of the ratio of the y component to the x component, which gives us -37.8749836510982 degrees.

Step 5 ：However, the question asks for the angle north of west, which is the same as the angle measured counterclockwise from the negative x-axis. Therefore, we add 180 degrees to the direction to get the final answer: direction_adjusted = 142.1250163489018 degrees.

Step 6 ：Final Answer: The direction of the displacement vector is \(\boxed{142.13}\) degrees north of west.