Considering it as a cylindrical wire you can evaluate its volume
Mass of the wire: 1 g
Density is defined as mass per unit of volume.
In your case, the density of the wire is known to be equal to
So, in order to determine the mass of the wire, you need to know what volume it occupies. You can assume it to have the shape of a very long and thin cylinder, so that tis volume can be determine by using
In your case, the wire hs a diameter of 0.002 m, which means that its radius will be
The wire's volume will thus be
This means that the mass of the wire will be
Expressed in grams and rounded to one sig fig, the number of sig figs you gave for the diameter of the wire, the answer will be
1 gram (CGS) or
assuming the wire is cylindrical:
Area of the cross section:
Total volume=area x length:
Total mass=volume x density:
The numbers were chosen to make the math very simple. The total mass is 1 gram.
Incidentally, this wire is made of a material with the same density as water (real metals are much denser).