First figure out how many miles over the speed limit Mark was going: 75 mph - 30 mph = <<75-30=45>>45 mph
Now figure out how much the per-mile fine is: $2/mph * 45 mph = $<<2*45=90>>90
Now add that amount to the base fine: $90 + $50 = $<<90+50=140>>140
Now double that amount for being in a school zone: $140 * 2 = $<<140*2=280>>280
Now figure out how much Mark owes his lawyer: $80/hour * 3 hours = $<<80*3=240>>240
Now add the court costs, lawyer fees and fine: $240 + $300 + $280 = $<<240+300+280=820>>820
#### 820