m-subharmonic and m-plurisubharmonic functions -- on two problems of Sadullaev

We show that the spaces of $A$-$m$-subharmonic and $B$-$m$-subharmonic functions differ in sufficently high dimensions. We also prove that the Monge-Amp`ere type operator ${\mathcal{M}}_m$ associated to the space of $m$-plurisubharmonic functions does not allow an integral comparison principle except in the classical cases $m=1$ and $m=n$. These answer in the negative two problems posed by A. Sadullaev.