Solve -1881*v + 23355 = 588*v - 30963 for v.
Solve this plz.

A: 22

Solve 6031*d + 45320 = 3971*d for d.
Solve this plz.

A: -22

Solve -4*n = 132 - 144 for n.
Solve this plz.

A:
3