a)
[tex]Obw_{ABC}=16+20+24=60\ [cm]\\k=\frac{Obw_{A_1B_1C_1}}{Obw_{ABC}}=\frac{12}{60}=\frac{1}{5}[/tex]
b)
[tex]|A_1B_1|=\frac{1}{5}*16=\frac{16}{5}=3\frac{1}{5}=3,2\ [cm]\\|B_1C_1|=\frac{1}{5}*20=\frac{20}{5}=4\ [cm]\\|A_1C_1|=\frac{1}{5}*24=\frac{24}{5}=4\frac{4}{5}=4,8\ [cm][/tex]
