Huaxin Lin 
$C^*$-Algebra Extensions of $C(X)$ 

This work shows that the Weyl-von Neumann theorem for unitaries holds for $/sigma$-unital $AF$-algebras and their multiplier algebras. Lin studies $E(X, A)$, the quotient of $/mathrm{{/mathbf{Ext}}}^{eu}_s(C(X), A)$ by a special class of trivial extension,