Answer
a. a nonmetal in group 4A
b. the inner transition metal with the lowest atomic number
c. all of the nonmetals for which the atomic number is a multiple of five
d. a metal in Group 5A
Work Step by Step
a. Carbon is the only nonmetal in group 4A. Silicon and germanium are metalloids; tin and lead are metals.
b. The inner transition metals are the elements that appear below the main body of the periodic table (the lanthanide and the actinide series). The inner transition metal with the lowest atomic number is lanthanum (57).
c. Neon (10), Phosphorus (15), and Bromine (35)
d. Group 5A has only one metal: Bismuth. Nitrogen and phosphorus are nonmetals, while arsenic and antimony are metalloids.