A wire having a linear mass density of $1\mathrm{.}07$ g$/$cm is placed on a horizontal surface that has a coefficient of kinetic friction of $0\mathrm{.}200.$ The wire carries a current of $1\mathrm{.}40$ A toward the east and slides horizontally to the north at constant velocity.

$($a$)$ What is the magnitude of the smallest magnetic field that enables the wire to move in this fashion?

T

$($b$)$ What is direction of the smallest magnetic field that enables the wire to move in this fashion?

$$ below the horizontal