$Q\frac{2}{}(12$ marks$){?}_{(})$

Answer the following questions briefly: $($Choose only two$)$

$1-$ What are the advantages of the Hydrothermal growth method?

$2-$ What parameters do the final crystal's perfection depend on using the growth from the

Gel method?

$3-$ What are the types of techniques for growing crystals from the vapor phase?