In a moving coil galvanometer,to make the field radial,what is done?

$A$ galvanometer having a resistance of $20\,\Omega$ and $30\,divisions$ on both sides has a figure of merit of $0.005\,A/division$. The resistance that should be connected in series so that it can be used as a voltmeter up to $15\,V$ is ........... $\Omega$.

In order to pass $10\,\%$ of the main current through a moving coil galvanometer of $99\,\Omega$,the resistance of the required shunt is ............ $\Omega$.

The deflection in a moving coil galvanometer is reduced to half when it is shunted with a $X \ \Omega$ coil. The relation between $X$ and the resistance of the galvanometer $G$ is:

$A$ galvanometer has a coil of resistance $100 \Omega$ showing a full scale deflection at $50 \mu A$. The resistance that should be added to use it as an ammeter of range $10 \text{ mA}$ is

The sensitivity of a tangent galvanometer is increased if