following are statements regarding the relationship between the magnetic flux density and the magnetic field intensity. [A]: The magnitude of the magnetic flux density is directly proportional to the magnitude of the magnetic field intensity. [B]: The magnetic flux density is directed along the direction of the magnetic field intensity. a. Both [A] and [B] are incorrect b. Only [B] is incorrect. c. Only [A] is incorrect.  d. Both [A] and [B] are correct. 2.)  Which of the following is invalid? a. more than one of the choices b. curl of a magnetic fields c. curl of charges d. curl of potential function

3.) If a steady current-carrying wire is subjected in a uniform magnetic field, which of the following is true

a. It experiences no force when directions of the current and of the magnetic field are perpendicular to each other

b. The force it experiences, the current, and the magnetic field are all perpendicular to each other.

c. The force it experiences is always perpendicular to both the directions of the current and of the magnetic field.

d. The answer cannot be found on the other choices.