Which of the following sulfate salts has the highest solubility in water?

Among the following,which is water insoluble?

Choose the correct statement$(s)$:
$A.$ Beryllium oxide is purely acidic in nature.
$B.$ Beryllium carbonate is kept in the atmosphere of $CO_2$.
$C.$ Beryllium sulphate is readily soluble in water.
$D.$ Beryllium shows anomalous behavior.
Choose the correct answer from the options given below:

The major ingredient $(51 \%)$ in Portland cement is

The number of water molecules in gypsum,dead burnt plaster and plaster of paris,respectively are:

$BeO$ reacts with $HF$ in the presence of ammonia to give $[A]$,which on thermal decomposition produces $[B]$ and ammonium fluoride. The oxidation state of $Be$ in $[A]$ is $.....$.