In all atoms of bismuth, the number of electrons must equal the:

1 number of protons

2 number of neutrons

3 sum of the number of neutrons and protons

4 difference between the number of neutrons and protons

Ascientist conducted an experiment and discovered that certain plants grow faster when given a particular amount of fertilizer. anouther scientist conducted the same experiment and got similar results. which concept does this best illustrate? a) repetition b) replication c) precision d) validity