#### Answer

(a) The magnitude of the maximum possible force is $2.16~N$
(b) The information enables us to calculate the maximum possible force in the case when the angle $\theta$ is $90^{\circ}$. However, the force could be less than this magnitude depending on the angle $\theta$.

#### Work Step by Step

(a) We can find the magnitude of the maximum possible force:
$F = I~L~B~sin~\theta$
$F = (18.0~A)(0.60~m)(0.20~T)~sin~\theta$
$F = (2.16~sin~\theta)~N$
The magnitude of the maximum possible force is $2.16~N$
(b) The information enables us to calculate the maximum possible force in the case when the angle $\theta$ is $90^{\circ}$. However, the force could be less than this magnitude depending on the angle $\theta$.