Deep water rises along the coast of peru to replace surface water carried away from the coast by strong winds. why is upwelling important?

It delivers nutrients to the well-lit epipalegic zone, stimulating photosynthesis.

Upwelling is a an oceanographic phenomena, in which high speed wind currents replaces warmer, nutrient depleted surface water with dense, cool, nutrient rich water from the bottom of the ocean. This process increases the nutrient content of the surface water or epipelegic zone. The epipelegic zone is the surface layer of the ocean. This zone receives the maximum sunlight. Upwelling process favors high biological activity in this zone because of the availability of nutrients and sunlight favor photosynthesis, responsible for the growth of large number of phytoplanktons.  

yes its like the dead sea which is full of salt which makes you stay afloat

so yes an egg will float in salt