How many significant digits are in this number: 0.0030670?

How might this scientific phenomena be explained? a paper clip floats on water.

How many moles of no2 will form when 3.3 moles of cu are reacted with excess hno3?

The density of the solid phase of a substance is 0.90 g/cm3 and the density of the liquid phase is 1.0 g/cm3. a large increase in pressure will a. lower the freezing point b. raise the freezing point c. lower the boiling point d. raise the triple point e. lower the triple point