Solving triangle

In ΔABC，b = 2.1cm，A=120degree and SinB：SinC = 1：2. Solve ΔABC
Sol
SinB：SinC = 1：2
SinB/1=SinC/2
SinB/2.1=SinC/4.2
SinA/a=SinB/b=SinC/c
Sin120度/A=SinB/2.1=SinC/ 4.2
C=4.2
ΔABC=(1/2)BCSinA
=(1/2)*2.1*4.2*Sin120度
=(1/2)*2.1*4.2*√3/2
=441√3/200

Solve the ΔABC means that find out all the sides and angles of the triangle. Thx.

find the angle? find the length of side?