A $U$ tube with both ends open to the atmosphere, is partially filled with water. Oil, which is immiscible with water, is poured into one side until it stands at a distance of $10\text{mm}$ above the water level on the other side. Meanwhile the water rises by $65\text{mm}$ from its original level. The density of the oil is:

1. A
   $650{\text{kg m}}^{-3}$
2. B
   $425{\text{kg m}}^{-3}$
3. C
   $800{\text{kg m}}^{-3}$
4. D
   $928{\text{kg m}}^{-3}$