Answer:
[tex]the \: net \: force \: on \: the \: desk \: will \: \\ increase \: by \: 30 \: newtons .\\ \\ the \: desk \: will \: only \: accelerate \: if \: the \: net \: \\ force \: applied \: to \: it \: is \: greater \: tha n \\ \: the \: weight \: of \: the \: desk \: in \: newtons.[/tex]