The length of time required for half of the radioactive atoms in a sample to decay is its. a. half-life. b. relative date. c. radioactive date. d. period.

n has four pairs of electrons in the valence shell, electrons repel one another ,n has 7 protons in its nucleus, and since n has 7 protons, it must fill the second shell, giving it 4 pairs of electrons. the electrons form 3 bonds and 1 lone pair of electrons. each pair of electrons repels the other pairs, so they are equally far apart.

so all of the above

the answer would be a