<h3>
Answer: 123 meters is the longest </h3>
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Work Shown:
Convert everything to the same unit. I'm going to convert everything to meters
0.1203 km = 120.3 meters (multiply by 1000)
1230 cm = 12.3 meters (divide by 100)
12030 mm = 12.03 meters (divide by 1000)
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The four distances we have are: 120.3 meters, 123 meters, 12.3 meters, 12.03 meters. We see that 123 meters is the longest.
