Answer 1

Yes a galvanometer can be used for measuring the current

Conversion of a galvanometer into an ammeter

A shunt (low resistance) is connected in parallel with a  galvanometer.

`S=(I_g/(I-I_g))G`

Here,

I = total current in circuit

G = resistance of the galvanometer

S = resistance of the shunt

I_g = current through the galvanometer