Convert the following lengths to kilometers and meters, and round to the nearest kilometer.

Here are the completed conversions and rounding for each row:

Row a:
Given: $411 \text{ m}$

Step 1: Convert meters to kilometers and meters.

$$411 \text{ m} = 0 \text{ km } 411 \text{ m}$$

Step 2: Round to the nearest kilometer. Since $411 \text{ m}$ is less than $500 \text{ m}$, we round down.

$$\text{Rounded value} = 0 \text{ km}$$

The completed row a is: $411 \text{ m}$ | $0 \text{ km } 411 \text{ m}$ | $\boxed{\text{}0 \text{ km}}$

Row b:
Given: $2020 \text{ m}$

Step 1: Convert meters to kilometers and meters.

$$2020 \text{ m} = 2 \text{ km } 20 \text{ m}$$

Step 2: Round to the nearest kilometer. Since $20 \text{ m}$ is less than $500 \text{ m}$, we round down.

$$\text{Rounded value} = 2 \text{ km}$$

The completed row b is: $2020 \text{ m}$ | $2 \text{ km } 20 \text{ m}$ | $\boxed{\text{}2 \text{ km}}$

Row c:
Given: $6 \text{ km } 373 \text{ m}$

Step 1: Convert kilometers and meters to meters.

$$6 \text{ km } 373 \text{ m} = (6 \times 1000) \text{ m} + 373 \text{ m} = 6000 \text{ m} + 373 \text{ m} = 6373 \text{ m}$$

Step 2: Round to the nearest kilometer. Since $373 \text{ m}$ is less than $500 \text{ m}$, we round down.

$$\text{Rounded value} = 6 \text{ km}$$

The completed row c is: $6373 \text{ m}$ | $6 \text{ km } 373 \text{ m}$ | $\boxed{\text{}6 \text{ km}}$

Row d:
Given: $9 \text{ km } 12 \text{ m}$

Step 1: Convert kilometers and meters to meters.

$$9 \text{ km } 12 \text{ m} = (9 \times 1000) \text{ m} + 12 \text{ m} = 9000 \text{ m} + 12 \text{ m} = 9012 \text{ m}$$

Step 2: Round to the nearest kilometer. Since $12 \text{ m}$ is less than $500 \text{ m}$, we round down.

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