In which of the following systems of units is $Weber$ the unit of magnetic flux?

$A$ coil of $100$ turns and area $5 \text{ cm}^2$ is placed in a magnetic field $B = 0.2 \text{ T}$. The normal to the plane of the coil makes an angle of $60^o$ with the direction of the magnetic field. The magnetic flux linked with the coil is:

If the magnetic flux is expressed in $Weber$,then magnetic induction can be expressed in

$A$ square loop of side $1\,m$ and resistance $1\,\Omega$ is placed in a magnetic field of $0.5\,T$. If the plane of the loop is perpendicular to the direction of the magnetic field,the magnetic flux through the loop is $\dots\dots$ weber.

When does the magnetic flux become zero?

$(a)$ Magnetic field lines show the direction (at every point) along which a small magnetised needle aligns (at the point). Do the magnetic field lines also represent the lines of force on a moving charged particle at every point?
$(b)$ Magnetic field lines can be entirely confined within the core of a toroid,but not within a straight solenoid. Why?
$(c)$ If magnetic monopoles existed,how would the Gauss's law of magnetism be modified?
$(d)$ Does a bar magnet exert a torque on itself due to its own field? Does one element of a current-carrying wire exert a force on another element of the same wire?
$(e)$ Magnetic field arises due to charges in motion. Can a system have magnetic moments even though its net charge is zero?