Answer:
65,900 mL
Explanation:
You want to know the volume in mL of a sink with a volume of 65.9 dm³.
Conversion
The relation between dm³ and mL is ...
1 dm³ = 1000 mL . . . . . . . . . . also, 1 L (liter)
Application
Multiplying the above relation by 65.9, we have ...
65.9 dm³ = 65,900 mL
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Additional comment
For many problems involving volumes in liters and dimensions in centimeters or meters, it can be convenient to convert the dimensions to decimeters (dm). Since 1 dm³ = 1 L, that can make the desired volume easily calculated.