W=weekly wage, H=hours worked. For H>40:
W=40*8+12(H-40)=320+12H-480=12H-160, so W=12H-160 where H≥40 is the gross weekly wage.
The first 40 hours are paid at $8/hr=$320. The remaining hours are paid at $12/hr.
D=tax deduction; D=(W-80)/4 which is 25% of earnings over $80.
N=W-D=12H-160-3H+60=9H-100. Net wage=9H-100.
(If H=60, N=9*60-100=$440.)