how many significant figures are in the measurement 0.00440 grams?

6
5
3
2

North atlantic current or north atlantic drift is the answer

If a hydrogen atom is neutral, it must also have  one electron. an oxygen atom (o) has an atomic number of eight (8). this means a neutral oxygen atom has eight protons and eight electrons. the element actium (ac) has an atomic number of 89, so it has 89 protons and 89 electrons in a neutral atom

The correct answer is "atomic weight".