Convert --→ 678,000 cm = ____ km.

Choose the best answer from the options below:
A 5.78 km
B 6.78 km
C 67.8 km
D 678 km

1 m = 100 cm:

To convert cm to m, divide by a hundred (or move the decimal point two places to the left).

1 km = 1000 m:
To convert m to km, divide by a 1000, or move the decimal point three places to the left.

To convert centimeters (cm) to kilometers (km), we need to divide the value in centimeters by 100,000, since there are 100,000 centimeters in one kilometer.

So, to convert 678,000 cm to km, we divide 678,000 by 100,000:

678,000 cm / 100,000 = 6.78 km

Therefore, the answer is B) 6.78 km.