Frenkel and Schottky defects are

Explain stoichiometric defects shown by non-ionic solids.

When electrons are trapped into the crystal in anion vacancy,the defect is known as

Explain metal deficiency defect.

The correct statement among the following,regarding defects in solids is:
$(1)$ Frenkel defect is favored by small difference in the sizes of cation and anion.
$(2)$ Frenkel defect is a metal excess defect.
$(3)$ Trapping of electron in the lattice leads to formation of $F$-centres.
$(4)$ Schottky defect has no effect on the physical property of solids.

Which one of the following compounds shows both,Frenkel as well as Schottky defects?