For a single phase transformer, we obtain U$1=220$V$,$ I$1=0\mathrm{.}40$A$,$ P$1=72$W for primary side and U$2=112$V$,120\mathrm{.}20$A$,$ P$2=18$W for secondary side for $100$W resistive load. Calculate the Cos & of secondary side of this transformer. Your answer: $0,210\mathrm{.}230,50$ O $0,61$ O $0,80$