Solve 897*c - 7116 - 49664 = -1942*c for c.
Solve this plz.

A: 20

Solve 2610*s + 21 = 2617*s for s.
Solve this plz.

A: 3

Solve -2*z + 10*z = 40 for z.
Solve this plz.

A:
5