Sketch enough representative vectors of a planar vector field F→ to illustrate the properties described in each of the following cases:
a. F→ is radial with magnitude increasing proportional to the distance from the origin and represents a repelling force.
b. F→ is tangential to circles centered at (2, 0) with magnitude inversely proportional to the distance to (2, 0) with flow lines oriented clockwise.
c. F→ is everywhere parallel to the y-axis with F→ (x, y) · (i→ + vj) = x + 2.