Some pieces of impurity (density=$\rho$ ) is embedded in ice. This ice is floating in water. (density=${\rho }_{\omega }$ ). When ice melts, level of water will

Level will fall if initially the impurity pieces were floating along will ice and later it sinks. (because the volume occupied by water whose weight is equal to the weight of impurity will be more than the volume of the impurity)

Level will remain unchanged if initially they were floating and later also they keep floating. ( In both cases the volume of the displaced water, whose weight is equal to impurity is same).