Why is the sky Blue?

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How many atoms are in 1.4 mil of phosphorus trifluoride (pf3)

Which are examples of how technology has advanced scientific understanding.1using hot water to sterilize medical equipment.2transplanting a human organ into another individual.3inserting genes from one sheep into another cell to make a cloneunderstanding the different structures that make up a cell.4examining microorganisms from the deepest parts of the ocean

The appropriate concentration for an iodine sanitizer is