<human>:  Sam bought a heavy safe with a combination lock. There were four rows with twenty gold bars per row arranged in the safe. If each gold bar is worth $20000, calculate the total worth of the gold bars in the safe.
<bot>: How many gold bars are there? ** If there were four rows of twenty gold bars arranged in the safe, the total number of bars in the safe is 4*20 = <<4*20=80>>80 bars.
How much are the gold bars worth? ** Since each gold bar is worth $20000, the 80 bars are worth 80*$20000 = $<<80*20000=1600000>>1,600,000
#### 1600000