Abstract: It is planned to present certain necessary and sufficient conditions for approximability of functions on an arbitrary plane compact set by functions, bianalytic on neighborhoods of the set, in the norms of Whitney spaces $C^m$ for all $m \geq 0$. The formulated criteria are given in the so-called individual form and for each $m$ they are formulated in terms of geometric measure theory.

Abstract: This is joint work with J$\mathrm{\acute{a}}$n Min$\mathrm{\acute{a}\check{c}}$. Let $F$ be a field. We show that any triple Massey product in Galois cohomology of $F$ with coefficient $\mathbb{F}_2$ contains 0 whenever it is defined. This extends a recent theorem of M. J. Hopkins and K. G. Wickelgren, from a global field to an arbitrary field.