a.

The force on an object is given by .

For , .

Graph the point  in the complex plane.

Then draw a vector with an initial point at the origin and a terminal point at .

Graph :

. 

b.

Use the absolute value of a complex number formula.

The absolutue value of is or about . 

Find the measure of the angle  that the vector makes with the positive real axis.

The magnitude of the force is about at an angle of about .

a.

Graph :

b.

The magnitude of the force is about at an angle of about .