Solve -55*o = -80*o + 250 for o.
Solve this plz.

A: 10

Solve 76915 = 2700*c - 38246 + 159099 + 145062 for c.
Solve this plz.

A: -70

Solve -13*f = -29*f - 18*f + 612 for f.
Solve this plz.

A:
18