Question

types of elements
the periodic table contains three types of elements: metals, nonmetals, and metalloids.

Explanation:

In the periodic table, metals are on the left - hand side and bottom - left regions. Nonmetals are on the right - hand side. Metalloids are along the staircase - like diagonal line separating metals and nonmetals. The top '?' region is nonmetals, the middle '?' region is metals, and the bottom '?' region is nonmetals.

Answer:

Top '?': Nonmetals
Middle '?': Metals
Bottom '?': Nonmetals