GeO₂ exists in a number of structures, most commonly a hexagonal form that is built on corner sharing GeO₄ tetrahedra and a tetragonal structure in the mineral argutite built from edge sharing GeO₆ octahedra.

(a) Which of these two GeO₂ structures will be favored if the sample is prepared under high pressure conditions. In framing your answer, you should comment on the likely difference of Ge-O bond distances in each structure. 

(b) Giving your reasoning predict if a direct transformation between the hexagonal and tetragonal structures is likely to be first order or continuous.